Please visit our Sponsors
FAQs on Koi, Pond Fish Breeding

Related Articles: Koi, Pond Fish Breeding

Related FAQs:  Goldfish Reproduction

Aquatic Gardens

Ponds, Streams, Waterfalls & Fountains:
Volume 1. Design & Construction
Volume 2. Maintenance, Stocking, Examples

V. 1 Print and eBook on Amazon
V. 2 Print and eBook on Amazon

by Robert (Bob) Fenner

Koi fry, dying       9/19/15
Greetings WetWebMedia crew,
I recently separated some Koi fry and added a few to a 150g aquarium. I'm noticing some of the fish in the 150g are whirling and I'm starting to notice some deaths.
Could this be a parasite?
<No; not likely. How recent is recently? I'd be adding a BUNCH of the pond water to this tank.... like maybe changing all of it out and replacing... STAT! As in right now>
If so, which one and what's best treatment. Also what would be best way to ID. I'm not seeing any outward signs of illness(aside from whirling). I have HexShield and Ickshield on standby, is there any harm in treating fish so young? Any help would be greatly appreciated. Thanks
<.... not parasitic likely, but environmental. Bob Fenner>
Koi fry parameters      9/19/15

I forgot to include parameters. This is a cycled tank with over the top filtration. Nitrates less than 10 due to the Aquaponic grow bed that filters this tank in additional to a few sponge filters. Water is moderately hard and have had no issues with my Koi in other tanks/ponds. Please help. Thanks again.
<IF it's not the water they were born in.... CHANGE IT OUT, NOW. Something in the tank is toxic. Bob Fenner>
Re: Koi fry parameters      9/19/15
The only odd thing is, I have a few other aquariums loaded with fry and only this tank is showing symptoms.
<..... RE read the last mail. B>
I have been separating them out for a few weeks. I do drip acclimate when transferring. This particular tank was holding a pair of cichlids that I removed 2 weeks ago, added heavy salt and let run without fish. I then lowered salinity to zero and added fry. I knew this was risky but because of grow bed, I didn't want to sterilize; this is the reason I suspected parasites. Thanks
Re: Koi fry parameters      9/19/15

Thank you for your input.
<Welcome! B>

Goldfish size for spawning / mystery fish in pond         9/8/15
Just wondering how big one year old goldfish are.
<Mmm; can be "dwarfed" to just an inch or so; or more than four inches under good conditions>

We have some new little fish in the pond which are a mystery because our largest goldfish are only 5 inches long. The new fish are brown,
<Start off as such>

the largest about one inch long. The likelihood of our goldfish being old enough to spawn is...not...we think.
But where could these new fish have come from???
<Likely are young from your existing... though "fish from the sky" (mainly water spout events) and trickster humans shouldn't be totally discounted.
Bob Fenner>
Re: Goldfish size for spawning / mystery fish in pond        9/8/15

Thanks for your reply! Very helpful.
<You're welcome>
I particularly like the waterspout theory...
<Am re-reading all "The Aquarium" mag.s... 1932 on.... there's quite a few summations, accounts>
The young are dark brown, the bigger ones lighter with pale bellies. Is that common?
<Ah yes; BobF>

goldfish; pond; selling excess spawn     2/4/15
My husband and I have a small backyard pond roughly 10 ft x12ft and 1 ft to 3.5 ft deep ( it is graduated)with waterfall, rocks and plants.
We started off with 6 koi and 5 goldfish and 1 Shubunkin. (We still have the 6 koi). We do feed our fish and the koi and goldfish seem to get along well.
The goldfish/Shubunkin population has exploded, they must love it!
But we do not want or think it is good to have that many goldfish, we probably have at least 50 maybe more goldfish.
<Ah yes; I'd be selling, giving away the excess. Perhaps local stores, CraigsList...>

We really cannot build another pond and if this keeps happening it would not help anyway!
The old pond at our old house had more frogs and perhaps that kept the goldfish population down??
<Yes; the frogs will eat small goldfish, minnows, fish period>
Can we sell the goldfish? What to do? Please advise. We live in Virginia.
thanks for any help!
<As above... try CraigsList first. Bob Fenner>
Re: goldfish    2/4/15

<Welcome. BobF>

Baby Goldfish!      6/26/14
Today In my pond I* noticed 2 one inch long baby fish. All I have ever kept in the pond are goldfish. Are these two baby goldfish?! I have a 500 gallon pond with 4 comet goldfish and 1 Shubunkin goldfish already in the pond.
Can I keep these two in the pond as well? Thank you.
<Can't tell from these photos. But if they're small, green-brown to bronze colour, and have the same basic shape as goldfish, then yes, they're babies. Baby goldfish don't turn gold until they're a few months old.
Cheers, Neale.>
Will the babies be ok in the pond?

I have a 500 gallon pond with 5 goldfish in it. 4 comets 1 Shubunkin. They had 2 babies.
<Ah, congrats>
I sent a photo earlier of them to you. Here is an improved version. And can these 2 new fish live their lifetimes together in the pond with my other fish? Thank you.
<Yes. B>

Emailing: Baby Goldfish! 6/26/14
They are a bronze color. Can I keep them in the 500 gallon pond with my 5 other goldfish?
<Likely so. If they've survived this far, their probably fine. Obviously the safest route is always to remove eggs and fry, and rear them indoors until they're an inch or so long.>
Thank you.
Re: Emailing: Baby Goldfish! 6/27/14

Thank you! :)
<Most welcome.>

Possible 3rd Baby Goldfish?    7/5/14
Last time I wrote about my 2 baby goldfish. But now I have apparently found a tiny 3rd fish. I caught it to examine it closer in a large specimen container before releasing it back into the pond. Here is the
best 2 pictures I took of it. It is tiny, about half the size of the other two I found. And it is gold in color in the light. Is it possible for goldfish to spawn multiple times in spring and summer? And how old do you
think the third fish is? Thank you.
<It's actually quite normal for pond Goldfish to spawn repeatedly across the year, often because the females will become "ripe" with eggs at different times according to size, age, diet, etc. Very small Goldfish are also at risk of being eaten, whether by the parents or by predators in the pond (Hydra, Damselfly larvae, Diving Beetles, etc) so you will likely on see a few fry survive from each brood. Colouration of Goldfish fry is genetic but variable given that most common Goldfish aren't pedigree fish
as such, so you're likely to get all sorts of fry if you keep a school of cheap Goldfish in your pond. Cheers, Neale.>
re: Possible 3rd Baby Goldfish?

Thank you Neal! :)
<Most welcome.>

At what age do baby goldfish eat with the adults?   7/9/14
Wanted to let you know I saw my 2 biggest baby goldfish feeding with the adults today for the first time. They are no longer the very shy and timid little babies I first saw them as. I think it has taken them about 3 weeks to become bold enough to eat with the adults. Is it normal for the babies to eat with the adults at a month old? Thank you.
<Not unusual... just need to be "larger than mouth size"... a half inch or so plus. B>
Re: At what age do baby goldfish eat with the adults?      7/10/14

Thank you Bob! :)
<Welcome Camster!>

Baby goldfish color change age?
My 2 largest and oldest baby goldfish are going through their color changes. (Largest one in the lower right of the picture I sent.) What at what age do pond goldfish usually go through color changes? Thank you.
<A few months. B>
Thank you Bob! :)

Controlling Pond Livestock Levels, algicides   7/11/13
I plan to have a small, shallow, sunken, round pond. It will be 3.4' in diameter by 3' deep. The pond will be 195 gallons. The pond will have 10 sq feet of surface area. The pond will have a submersible flat box filter filled with pea gravel. The filter will be rated for 50-250 gallons. The filter will be attached to a 306 gph submersible pump and fountain kit. I plan to use a plant and fish safe algaecide
<There is no such thing... Might I ask, what is this magic material?>
 to control algae. Possibly add a uv later. I plan to scrub the algae and do a partial water change once a week. Water ph will be 8. I plan on keeping 3-8 comet goldfish. I plan to clean the whole pond once a year, in the spring. I plan to clean the filter once a week to once a month.
I live in the Arizona desert.
My question:
What do I do when the fish in my pond become too numerous?
<Remove them... trade them to a local fish store, other hobbyists>
I already heard of these solutions:
1. Using spawning mops to collect eggs, then boiling the spawning mop to kill the eggs, then feeding the eggs to the fish.
<No; don't do this... won't work and will pollute the water>
2. Giving the fish to a store that sells them.
3. Giving the fish to a breeder or trader.
4. Giving the fish away to people who want them.
5. Euthanasia. I really do not want to try this one. Especially if the fish is healthy and surviving well on its own.
I cannot put them in another aquarium inside my house either.
Any other suggestions on what to do with pond fish I cannot keep in my pond?
Thank you.
<Numbers 2-4. Bob Fenner>
Re: Controlling Pond Livestock Levels... NOT algicide, but preventative      7/11/13

The magic substance is a Tetra brand pond algaecide.
<Ah, thank you. Searching on the Net re active ingredients I find this disclosure:
"It is made of the effective natural substances (peat and barley straw)"... Can be seen here:
It comes in a green bottle. Doctors Foster and Smith website has it for sale along with other pond and pet products. And thank you for your reply.
<These materials are "magical"; in that they do help prevent algae proliferation AND do appear "safe" in many settings. I encourage you not to wait till there are such, but to use the product per instructions, as a preventative. Bob Fenner>
Culling Comets    7/12/13
My round pond will be 3.4' in diameter by 3' deep.
It will have a butyl liner.
It will be shallow.
It will be 195 gallons.
It will have a surface area of 10 sq. feet.
It will contain comet goldfish.
It will have a 2' wide standard red brick edging.
It will have a submersible filter, 306 gph pump, and fountain kit.
The filter will have pea gravel media in it.
I live in the Arizona desert.
If my comet goldfish breed, how do I properly cull them?
<...  see WWM re Euthanasia>
Also, can I control pond algae with liquid treatments alone?
<Not likely; no.
.. PLEASE stop writing w/o looking, searching on WWM first.... see Pond Algae Control...>
Or would I still need a uv? Do I use both?

Questions on how to properly house Koi fry until my pond is built    8/4/12
Hello folks,
I have recently moved from Virginia to Florida, and had acquired 14 Koi fry right before my move.
<Fry? How small>
They made the 14 hour trip in the moving van just fine (I was scared to transport them, but stuck an air stone in the bag that was on the whole trip and they made it!). I have since put them into a 10 gallon aquarium until I get my pond designed and built here at the new house. I have not had good luck lately, in the past week 2 of my babies have died, oddly enough they were 2 that I considered to be the strongest and fastest growing of the bunch. All are under ¾" long. I have one that is stunted - the same size as when I got him in the middle of June. There is also 1 small Cory cat in the tank to help with cleanup. =)
<Should be fine... do know BTW, that fishes period, cooler water species more so, often have a lag time in showing stress... dying days after an insult/challenge>
I have had problems with the tank being cloudy, even while doing daily 40% water changes. The nitrites and ammonia were pretty bad for about a week, but are now finally getting under control. Here are the readings currently:
Nitrate - 0
Nitrite - .5
<Needs to be 0.0>
Hardness is at 0 - we have a water softener system on the house... I don't know how to fix this (?)
Alkalinity - 300
PH - 3.4
<No... please check again... needs to be neutral to slightly alkaline... 7-8 or so>
My questions are:
Should I get a preformed "water garden" container for them instead of the tank?
<A ten gallon should be fine for a couple, three months... w/ moderate feeding, regular (small percentage... 10-20%) water changes>
The filter just doesn't seem to be cutting it to me. On that note, how can I find a filter for one of these container gardens that will not suck my babies up?
<Look into a sponge type>
If they are in a larger container garden, do they actually need a filter, or just plants and air?
<Koi need a 24/7 filter, water movement>
The guy I got them from did NOT have a filter in place.
Should I keep them where they are, and if so, can you suggest ways to fix the problems with my water? Maybe upgrading to a much better filter?
<Yes to the better filter, an additional one>
I am feeding them twice daily (they are little piggies usually - but not so much as when I first got them) Omega One Natural Protein Formula Super Color Flakes for tropical fish
<Need lower protein... less than 20%... pellets are better than flakes>
as I cannot find a food specifically for Koi that is small enough for them to eat. I crush the flakes before feeding. Any suggestions here would be greatly appreciated.
The last baby that died had blood in his eyes...
<Likely the ammonia and/or nitrite>
yesterday he swam listlessly for about 30 seconds and then was fine. I thought maybe he hit his head on the tank. One other baby had done this a few days ago, but he is fine. He did not have the blood in his eyes while he was alive.
Thanks so much in advance for your comments/suggestions!
<Welcome. Bob Fenner>
Re: Questions on how to properly house Koi fry until my pond is built     8/14/12

Hi Bob  =)
Last I wrote I was having issues with pretty much everything.  I am happy to report no more casualties, both nitrates and nitrites are at 0, Hardness is now "hard" instead of soft, PH is 8.4.  I have changed their food to a floating stick that softens... they love it.  It had the lowest protein formula I could find, at 28%.
I've upgraded the filter - and the water is spectacular.  I bought a plant for the piggies to munch on.
Now one of the babies has what appears to be ick on his tail.
<Don't panic! And don't treat... if one "dot", not Ich, nor likely parasitic... most likely just a physical "bump">
 I'm not quite sure he could get this from a plant, but I have no other idea where it could've came from.
Should I pull him out?
 Should I treat the whole tank (and if so, any suggestions would be much appreciated.)?
Thank you in advance for all of your wonderful help!  You guys are true lifesavers!
<Welcome. BobF>
(PS - you will get a bounce back email that I don't exist... I assure you I do.  =)  )
Re: Questions on how to properly house Koi fry until my pond is built     8/14/12

Hi Bob,
Wow that was a quick response!  I just wanted to make sure - don't add any salt or anything to the aquarium?
 After staring at my little guys tail for awhile - it appears to have a moldy type look to it... its probably the size of a pin head - but the fish isn’t that big  ;)  It looks raised when looking at him from an angle.
I just don't want my babies to die. 
Thank you for all your help!

Aggressive behaviour in goldfish, pond  7/21/11
I have recently added a comet, a ghost Koi and a canary goldfish to my 10 by 4 by 3ft depth pond. The original five (a Shubunkin and four goldfish) are chasing the new ones relentlessly. The ghost Koi has taken to hiding but the other two are being hounded. The fish are all of a similar size (3-5 inches). The pond has a filter and a waterfall and is plenty big enough. Could this be breeding behaviour and if so why didn't it occur before the recent additions?
<Is likely reproductive related... though the comet-type gold fish and Koi are too small to be reproducing. And just the introduction "did it">
If it is aggression, will it pass without damage or should I take some action?
<I'd add at least some decor, floating plants, sunken block, brick... to "break up" the environment, give places to get out of view. Do separate the "losers" if they're apparently getting too beat up>
I hope you can advise.
Many thanks
<Welcome. Bob Fenner>

How to prepare an old oil palm plantation for fish breeding? 12/4/10
Dear Sir,
I am breeding some fish in Malaysia. I currently bought an Oil Palm Plantation which already non productive.
<Ahh, have seen the proliferation of such "mega plantations" on Saba>
By removing the palm tree, and clearing the location, now I start to dig a pond size of 30 x 60 feet.
The problem is that, the fish do not breed after 1 year, which my old pond having no problem.
So I started to use water to clean the base and find awfully smell coming up.
<Mmm, trouble>
I need your advice, what should I do, as I believe the previous oil palm chemical still there, and that cause the fish not breeding after so long.
Oxygen and PH is good.
Best Regards,
Kelvin Lau
<What species of fish/es are you trying to breed Kelvin? Have you tried digging further down to find "fresh" soil? Are you familiar w/ clays that can be applied, dished-in to make the basin inert? Bob Fenner>
Re: How to prepare an old oil palm plantation for fish breeding?   12/6/10

Dear Bob,
I am breeding Arowana Fish.
<... Scleropages formosus I take it... Are you maintaining females and males separately? Using hormone injection? What are you feeding? What is your method for reproducing?>
We tried to dig by washing away the smell and oil and taking out the roots of oil palm which bury quite deep. But need more solution, meaning after "washing", is there anything we can spray on, or any chemical needed to neutralize the soil.
I not familiar with using Clay.
<This... either "just" clean soil or a sealing kind. Read here re clays for pond sealing:

Overwintering first year young 11/17/10
Hi, I have a 460 gallon outdoor pond with comets. Within the last couple of months there have about 10 new baby fish that I have noticed. My pond freezes about 2" thick with a 4" hole in the middle from the pump which runs during the winter months. Will the baby fish survive the winter, they do not appear to have much meat on them. If they will not what do you recommend I do, thank you.
<Mmm, if you have a system of size (twenty gallons or more) that you can set up... soon, before the weather gets even colder... I would move these young in-doors (or the garage) for the winter to be sure. Do use existing pond water for the move, new system. Bob Fenner>
Re: Overwintering first year young   11/17/10

Thank you for getting back to me I really appreciate it. I have another question. Could I use on of those floating warmers that prevents the pond from freezing and if so would I feed any of these fish?
<Mmm, yes to the first, not really to the second. Do read here re overwintering ponds:
and the linked files above. BobF>

Pond predators... no marks... maybe not   8/11/10
Hi, I have a predator that is taking fish out of the pond, but not eating them. I have found two of my larger comets lying on the grass a foot or so from the pond's edge with no apparent damage from teeth, beaks or claws.
Are my fish jumping out on their own?
<Very likely so... tis the season for such exuberance ala reproductive behavior. I'd lower the water level several inches if you can, or put up a small perimeter fence to help them bounce back in. Bob Fenner>
Thanks Ron Norris, Litchfield IL

Baby Koi [Bob, any comments on Koi fry?]<<RMF>>  716/10
The last time we talked was back in Nov. of 09...and I had a rather large Koi, suffering from swim bladder disorder, and he ultimately lost his struggle to survive.
<Too bad.>
I now have something new I have never encountered, and would like some guidance. We have a Baby!!!!
I have only seen one fry to date...and it is about 1 to 1.5 inches long. I am somewhat surprised that there only appears to be one survivor...but nevertheless, we are thrilled to see the little guy swimming around the pond.
<It's always nice to see baby fish.>
Is there anything we should be doing as far as feeding differently because of the little one?
<Not really. Several high-protein meals per day are required, much as with any juvenile fish. Rearing Koi isn't too difficult, but they are more sensitive to low temperatures than adults. Serious Koi breeders will often rear them indoors in heated aquaria, around 20 degrees C/68 degrees F being ideal. The fry and yearlings often won't survive cold winters, so it's best to keep them indoors for at least the first year. Of course if you live somewhere warm all year around, like Florida or Southern California, that might not be necessary. This is somewhat different to Goldfish, which produce fry that are much more tolerant of cold, in part because they grow rather faster.>
Obviously our regular staple food to way too large for the baby. I am guessing that he/she is eating algae or something but have no idea what.
<Yes, they will eat algae, but a good growth rate depends on protein. When reared indoors, hard-boiled egg yolk is a classic foodstuff for juvenile Koi. Otherwise good quality flake food, 2-3 times a day, should do the trick.>
I do not have a separate tank to put the little guy in..and doubt I could even catch him/her.
<Indeed, this is always the problem when fish appear in the pond.>
We are very hopeful we can keep the youngster and watch as it matures....but optimistically cautious at the same time.
<Oh, yes, you can be optimistic given how big it is, but I have reared Crucial Carp fry, a related species, and found they didn't really become "hardy" until they were at least 2-3 inches long. If you can bring the chap indoors, that'd improve your odds. But with that said, if you live somewhere the water temperature doesn't drop below 15 C/59 F, your little chap should feed continually and that will ensure it gets through the winter.>
I look forward to any advise you can offer.
<Cheers, Neale.> <<I would leave this individual youngster where it is. It will grow an inch or more during this current warm season and be fine where it is. RMF>>
Re: Baby Koi [Bob, any comments on Koi fry?]  716/10

Thanks for the info....unfortunately we live in southern Indiana...and it does get rather cold here in the winter....certainly can see temps in the 40's F..for weeks...and as low as 0 F for short periods (a few days).
<The odds on his survival for the first winter are low.>
Snow is not unusual!!! Brrrrrr.....
We will be good temp wise for at least another 3-4 months, but Dec, Jan, and Feb will be cold.
I will see what I can find at my local pond supplier for protein....was even considering frozen brine shrimp...which is what I used when I had a saltwater tank. Otherwise...will use the egg yoke as suggested.
I may resort to getting a small indoor tank...10-15 gal....and try to catch the little guy before bad weather sets in.
<Probably wise, but do get the biggest tank you can... need not be an aquarium as such... a large plastic container that contains 20 gallons or more would be fine, provided it were filtered and, if not in a warm room, heated. Does rather depend on the circumstances.>
Thanks for the advice...will keep you up-to-date on progress. Nice talking with you again as usual..especially with good news instead of a serious problem.
<Indeed. Glad to help, and good luck.>
<Cheers, Neale.> <<RMF would still not move this fish... Likely it "came into being" last summer... Can/will live, over-winter in this setting>>
Re: Baby Koi [Bob, any comments on Koi fry?]   7/17/10

I do have a 55 gal. aquarium...but I have African Cichlids in it.....I think the fry's chances of survival would be worse than leaving him out in the cold.....don't you think??
<Bob Seems to think the juvenile will be okay overwintering outdoors. I strongly disagree, but he's more expert at Koi than me, and my experience is, to be fair, with wild Cyprinus species rather than the Japanese domesticated version. So you may decide to follow Bob's advice, leave the juvenile where he is, and see what happens.
Cheers, Neale.>

how to prevent Koi eggs from getting in my veggie filter   6/30/10
I have a 6,000 gallon Koi pond with a raised veggie filter at one end. I am very pleased with how the veggie filter helps with the filtration and allows me to have plants that otherwise my 2 ft. long Koi would not allow within the pond ! But I have just taken 61 small Koi out of the veggie filter. Apparently the eggs went through the skimmer and some ended up in the veggie filter. I don't want any more fish so can you tell me how I can prevent this from occurring in the future.
<Mmm... how to prevent your fishes from spawning? Separate the males from female Koi is what most folks do. Standard practice in the culture part of the trade in Nishikigoi. Otherwise, you might try supplying useful spawning
media for them, removing the fertilized (sticky) eggs...>
I found homes for the fish but did not enjoy having to catch the little guys in the veggie filter since it meant tearing up the plants to get them! Thanks for any information you can give me. Carolyn Wagnon
<Please read here:
and the linked FAQs file above. Bob Fenner>

Roe, roe, roe   6/28/10
Folks, would you like either of these for the gallery? This pickerel rush was afloat---my10-12" goldfish uprooted it in their carnal frenzy.
Annoyed, I prepared to repot it, only to discover the load of eggs on the roots. Change of plans! It will remain in isolation for a few days.
Max Smith
<Ahh, thank you for sending these along Max. Will post, share. BobF>

how to know if my baby Koi will have butterfly tails   6/3/10
Hello, Thank you for such a wonderful and informative site.
<Kind of you to say so.>
My story is that three of my Koi have spawned eggs at different times and I now have @15 baby Koi of different sizes.
I have two male Koi in the pond, one is a 4 year old butterfly and the other 18 month old Koi with a short "regular" tail and fins.
<I see.>
My question is at what age or size will I be able to tell if these babies will have the butterfly tail or not. All the females do not have fancy tails or fins.
<The butterfly gene is not completely dominant or recessive, so it's difficult to say whether this fault will occur in any particular offspring.
For this reason, if you're a serious breeder, you won't place butterfly Koi with your females because of the risk the offspring will carry butterfly fin genes. With that said, the long fins should be apparent quite early on,
within 6 months certainly, though there is an environmental dimension to the situation as well. If conditions aren't perfect, secondary infections can reduce the length of the fins. While the genetic fault responsible for the butterfly fins doesn't seem to make Koi noticeably weaker than proper Koi, like all long-finned fish poor circulation in the fins means they're more vulnerable to damage and secondary infections, especially during cold winters. In that sense then they're a lot like fancy Goldfish which shouldn't be kept outdoors during freezing weather.>
Some of the babies are about the size of an average males thumb, while others are the size of minnows.
<The presence or absence of the fault should be visible by the time they're 2-3 inches long.>
Thanks so much for your time,
<Hope this helps, Neale.>

Koi With Eggs in Fall 12/12/09
I have a koi (approximately 16" long) filled with eggs. The temperature has dropped dramatically in the past few days, and all the fish including this female have settled to the bottom of the pond. Is there anything I should do about this fish.
<Mmm, no. Leave it be as it is. Likely the eggs will be resorbed... Moving this fish, manipulating its environment at this time of year will only harm it>
This is my fourth year with this pond, and this has never happened before. They have always spawned in the spring/summer. Thanks for advice.
<Perhaps more evidence of change/s in our weather. Peace to you (and the world). Bob Fenner> 

Koi Eggs 5/15/09
Hello, I have recently moved our koi into a new outside pond. They seemed to love it after a few days, the larger females laid what seems to be a million eggs. The clear water that I had is now mucky, green and smelly.
<Quite normal when Carp are kept, whether those we call Koi or the standard issue, Nature's own Cyprinus carpio. Besides being big fish that produce a lot of solid waste by dint of their herbivorous tastes, they are also
"grubbers" that constantly sift mud and silt from the substrate. In natural bodies of waters this is actually a real problem if Carp are accidentally introduced, because the silt in the water column stifles plant growth, making the pond or lake unattractive to fish that need clear water environments, such as minnows. When keeping Carp in garden ponds, it's inevitable that the aquarist also installs a seriously heavy-duty filtration system with robust mechanical filtration to trap the silt, and moreover, if you want any hope of keeping the water clear, you make darn
sure that the bottom of the pond is essentially silt-free. There's no point at all keeping Carp in ponds with muddy or silty substrates: you'll never see them!>
I didn't realize that the fish were females so I wasn't expecting to have this problem, especially so quickly. Is there a way to get rid of the eggs, I don't want any fry this year?
<Short of manually removing each of hundreds of eggs, no, you can't "get rid of them" directly. That said, most will be eaten by the Koi and likely anything else in the pond. In the UK at least, a Tench will do well in a properly maintained pond (if anything, it's even hardier than Carp) and will eat any eggs it finds. Of course, it's as much of a shoveller as the Carp, so again, if you already have a silt problem, adding a Tench won't help any.>
I had to drain the pond about two days after they were laid because I think the growth of algae from the eggs was depleting the oxygen levels dramatically. I cleaned out some of the eggs, but it was impossible to get them all. The water is still mucky from them, and every morning the top of the water is covered in a white foam.
<Pond skimmers are available, and widely used by the more dedicated Koi keepers. They're not cheap, but they will remove organic material from the water, minimising foaming.>
By mid morning most of the foam is gone. Any information on how to clear this mess up would be great. Thank you.
<Probably your only option here is cleaning the pond and installing a very robust filtration system. Cheers, Neale.>
thank for the information
<Happy to help. Good luck! Neale.>

How can I tell if the fish is a KOI or a crossbreed? 5/13/09
I have used your website for years - researching information about my salt water fish tank. I have also bought your books! I love them. I know you know your stuff. I was very happy when a Google search on my pond question brought me to you. (and a little embarrassed that I didn't think of your site myself!) Thank you for all your past help and hopefully in advance for this email.
My pond is in the process of being rebuilt. It is going from 1500 gallons to about 4800 gallons and going high tech with new filters, lights, etc.
My largest Koi (6 of them) are about 5 years old and 23 inches long. I had 1 fancy goldfish in the pond with the KOI. I caught her recently and gave her away to a new home.
<This is best>
Since all the fish are awaiting the new pond, they are now located in large tubs. Last year was a banner year with babies and I would like to cull out the gold fish cross breeds (I have new homes waiting for them)- but I do not know how to tell which ones they are.
<Mmmm... not hard to discern with a bit of practice... but...>
I have been told that only Koi have whiskers, - is this true?
<Much more prominently, yes>
I read on your site that the Koi will be torpedo shape, but the shapes are too close for me to tell. Is there any other way to differentiate between them?
<The size, shape of fins, body conformation as you mention are most definitive... but...>
Thanks again for your help.
<I encourage you to study a bit more re such culling... is really an art and science... and necessary for good husbandry in our limited volumes. Bob Fenner>

Bob Fenner: deja� vu 8/25/08 Dr. Bob, Do you recall that you helped me in May (see email, "Whoever wrote...," May 18), with a Sarasa goldfish we call Beatrice, that vanished and reappeared 11 days later, with serious abrasions? <Yes> Bea is fine and healthy, thank you, although her scales haven't grown back yet. I'm sure you're aware of that timetable. <Yes> It's "Ben" this time, she's our alpha female, that disappeared 10 days ago, and showed up this afternoon, looking much the worse for wear. In fact, the photos don't show how ragged she really looks. So, as Bea survived so well, this time, we won't panic. We're close to the end of the spawning season here---we're in Zone 7, near Phila., PA. We'll just keep the water healthy. We'll figure we picked up a twofer on your advice in May. Thanks, Max Smith <I suggest you add some purposeful spawning media (see books... the Net re...) to break up the environment, reduce the amount of damage your stock causes itself thrashing against the rocks... and likely "thin the herd". B>

Re: Bob Fenner: deja vu, pond goldfish env. dis., repro.   -08/27/08 Thanks, Bob. I had found the mop head idea intriguing, but had dismissed it, because I had no plans to breed professionally. <I see... perhaps some floating plants instead... Water Lettuce, Hyacinth, Myriophyllum, Ceratophyllum... would work> It hadn't occurred to me that the use of media would protect the breeding fish. <Oh yes... easier to be driven into than the pond edges> In re: culling the herd: To those who plan to do that: Don't name your fish. Then it becomes Sophie's choice. Max <Heeee! Like many cultures, ours included... Children are not named till sometime after popping out. Cheers, BobF>

Spawning fish? 05/24/08 Hello Bob, <Howdy> I have been reading some of the questions from people like myself on fish and ponds that you so readily respond to. I am a new beginner on ponds and fish. I eventually want to have only a collection of Koi. I hope you can answer these simple questions for me: <Will try> I have a pond that holds approximately 1750 gallons. It is 4 feet deep and holds #4 Koi aging from approximately 6 months to one year old. #3 Sarasas, #2 Shubunkin that are in their 3rd year. Two of the Sarasas seem to be ready to spawn as one males was chasing them last weekend nudging and being quite aggressive with the females. Since then all is quiet and the females still seem so swollen. My question is how long before the eggs are laid? <Mmmm, "soon"... depending on how actual ripe the females are, the water temp...> If they already have, how long before I see signs of the fry? <Mmm, likely a couple of weeks... for the fry to hatch out, grow enough to be seen... You should read on WWM re pond fish reproduction...> Do I need to pull out the plants to see where the eggs could have been laid? How long is it before the fry hatch from the eggs? <... all posted: http://wetwebmedia.com/PondSubWebIndex/pdfshbreeding.htm and the linked files above...> I have ordered a spawning net for the pond, when it arrive should I put the fish in the net? <Mmm, no... not the purpose of such> I appreciate your expert advice. Sincerely, Susan <Keep reading Suze... BobF, still out in Germany>

Pond, goldfish, repro...   10/12/07 Hello...I have a rather large pond - 40' X 60' in Sisters, OR...in it live about a dozen rather large goldfish, most of them nearing a foot in length. There is a rather pregnant goldfish who seems to be suffering trying to eliminate the mini fishes within. <... eggs perhaps> A neighbor mentioned something about attaching a sponge to the side of my pond that would allow her, I am guessing, to rub against it in lieu of the males doing their job. <The birth control sponge?> Have you heard of this and, if so, does it work? More importantly, if you are aware, what do I need to do to attach the sponge properly allowing her to rid herself of said mini GF's? <Never heard of either such a device, or mini fishes...> Thanks for your response (and, hopefully, you've stopped laughing now) as you can see I am quite stumped. blessings, Kels <Read here: http://wetwebmedia.com/FWSubWebIndex/gldfshreprofaqs.htm and the linked files above. BobF>

Koi/Goldfish cross-breeding   9/12/07 My husband says goldfish and koi don't inter breed, is that true? We have both and now we have babies, which are rather dull looking so we were wondering. Thanks Teresa <These two can indeed cross. Some places their resultant young are called (golden) orfes... though this name is also applied to other cyprinid species. Do know that even "pure" goldfish or golden koi/Nishikigoi produce some percentage dull-colored young per batch as well. Cheers, Bob Fenner>

Goldfish mating, pond   7/14/07 I've spent the last hour reading many of the questions and answers provided here. What a wealth of information! It is all rather overwhelming though, and because of different pond sizes, fish breeds, climate zones, I'm not sure I'll ever find the 'right' combination fit for my situation. So with that in mind, I'll ask my question! <Okay> I have an outdoor pond, live in the White Mountains of New Hampshire, so very cold, long winters. The pond is approx 450-500 gallons, 1 foot deep, step down to 2 feet deep, which then steps down to 3 feet deep. <Yikes... a small volume... I do hope you have measures (plural) in effect to prevent total freezing> I dug it last spring, lined it, set up equipment which consists of a skimmer, CalTech 1000 pump and a CalTech filter & ultraviolet light system, which empties to a natural stone waterfall. There are two baskets of lilies, and one basket with a Canan. There are also several 'folds' in the heavy duty liner I have, which the fish hide in often. <Mmm, okay> I then stocked it with six feeder fish from a pet store, and was told (not by the pet store) that the feeder fish are 'Comets". <Yes... a variety (all goldfish, like domestic dogs... are the same species) produced in America> One is solid orange, the others are orange and white, ranging from mostly white with one orange spot to mostly orange with one white spot. All have fairly common fins/tails, except one has very flowing fins and a very large flowing tail. They were approx 2" long when I put them in the pond last June. One did not survive the Nor'easter we had here in April of this year. The pond had completely thawed, then froze again during the Nor'easter. Although it was still fairly cold when the pond thawed, and I was not feeding them yet, one apparently didn't go for cover again during the storm, and he/she froze to the bottom of the ice during the storm. Throughout the winter I kept a Thermo-pond 3.0 heater in it just to keep an open hole in the ice for escaping toxins. This heater was still in the pond during the nor'easter. <I see> The pond is very clean, I clean the filter once every two weeks, and I've had no algae blooms this year (add the ultraviolet light this year because of fighting algae blooms last year). There is moss growing on the rocks of the waterfall, which did not happen last summer, and I have to wonder if it's because the water is so much cleaner after adding the ultraviolet light. <This and natural succession... the "moss"... providing kinds of competition> There are also numerous red spotted newts in the pond at any one time, although the most I've seen has been six. There is also a small hornpout that the kids caught in a nearby lake last summer, only 1" long when we put him in the pond, and now over 3" long. <Neat> Since we lost one of the six original fish, I purchased two more feeder fish, these black and orange, a couple of weeks ago, and they are currently about 2" long. The original five from last year range from 4" to a little over 5" long. There appears to be 4 male and one female, whom the males seem to chase relentlessly - all part of mating I know. About a month ago, a large toad took up residence and spent all night calling a very large female toad to the pond, where they spent all of the next day laying their stings of eggs. The eggs have since hatched, and the baby toads are now close to leaving the pond, although probably only about 50 or so have made it past the tadpole stage. I've read that fish do not eat toad tadpoles, only frog tadpoles, and this seems to be true. The fish have all ignored the tadpoles, with a few exceptions of sucking them into their mouths the first day they hatched, only to spit them right out again. Seems most of the tadpoles in the early stages were sucked up by the skimmer/filter system. Anyway, to make an even longer story longer, three days ago I found a small blackish brown fish, about an inch long, and of course I'm assuming it's a baby goldfish. When I first saw it flitting about, I though it was a tadpole - a few still have very long tails while most have lost their tail. But once it 'settled' somewhere, I realized it was most definitely a fish. I've watched many times in the last few days, trying to see if there are more, but this appears to be the lone survivor from any fry the one female has produced. I know the mating season goes on all during the warm months - which fortunately for the female isn't too long up here. However, they seem to chase her almost daily, and with four of them verses only one of her, they seem to 'tag team' her. They get a rest, but she doesn't. She has no damage to fins or tail, and she does often get down in a fold of the liner where they can't get to her. She'll rest there for 10-15 minutes, then come back out for the chasing to continue. The chasing usually lasts 2-3 hours from what I've observed, but will happen 3-4 times a day. Often in the evening/early morning the hornpout will follow the female around as well during this frenzy, perhaps eating the eggs as they are dropped? <Likely so... and other organisms (insects... mostly) are likely consuming them as well> The hornpout is only out & about in the very early morning and the late evening - apparently is a night feeder. <Mmm, as are most Ameiurids, American catfishes...> Although I feel for this poor female, she does not appear damaged, and often only rests a short time during these chases, despite the fact that she can get away from them. When they 'pin' her to the bottom of the pond and 'roll' around on her (an act that lasts from start to finish approx 2-3 minutes), she has many opportunities to get away while they take turns 'rolling' on her, but she seems to just stay on the bottom of the pond until they all swim away, then she swims off. She is the largest, most beautiful of the bunch, and I really do not want to find a new home for her nor do I have any place to set up an additional pond for just her. I am hoping that at least one of the two new fish, and perhaps the one lone fry, will be female, and the odds will be a bit better next summer. In the mean time, do you think she will be okay for the next couple of months? <I do think so, yes. As you state, there is apparently no damage...> Will the size of the pond along with the hiding areas in the folds of the liner provide her enough protection to rest and get away from the 'brutes'? <Hopefully yes... IF this fish did look beaten, I'd fashion a floating net to keep the other fish away...> By Sept, it will be cold enough here that the mating should stop. It has currently been going on since the middle of June, so about one month. Thanks so much for taking the time to read all of this, and for any suggestions and/or comments you can provide. Holly <Thank you for writing... so fully, lucidly. Bob Fenner>

FISH FARMING (KOI)  7/4/07 Bob, I read your article on the net, about Koi & pond fish breeding. I have a 3/4 acre spring fed pond, My kids gave me 13 Koi for Christmas 3 yrs. ago. They are thriving, now we have about 70 beautiful Koi. They are all healthy & have Japanese markings/colors. Could you tell me where I can get info. on fish farming, how to get them out of the pond, about holding tanks etc... <The best method involves a large, appropriate-mesh size, softish barrier net (Memphis Net and Twine et al. sell these pre-made with a float and lead line)... two poles for keeping open/flat... and friends to help pull... hopefully your pond basin is flattish...> I'd like to start a small business. I would appreciate any info. you could give me, perhaps you know of someone that would be willing to "take me under their wing". I live in West Michigan-not far from Lake Mi. Thank-you! Sincerely, Harvey French <Mmm, well... there is a bunch to all this... from knowing the "blood lines" of the fish you have and will have (takes years), granting you an idea of what sorts of percentage varieties you'll likely produce... keeping the sexes separated, culling vigorously... To aspects of business... who will you sell to? How will you make delivery? To legal matters... some States are leery of Koi/Carp (the same species, Cyprinus carpio) getting loose... For a good general idea of what you're up to, take a read through your local library for the many books on Koi/Nishikigoi... "Living Jewels" is a fave... Bob Fenner>

Pond breeding or not   7/4/07 Hi. <<Greetings Patty. Tom with you.>> I have five goldfish in a 800 gallon pond that has a circulating pump that channels water to the far end of the garden where if flows back through an ornamental spring. I have sunk a few old pots on their sides in the hopes that they might provide shelter if fry appear. The fish are chasing each other madly all day and I've yet to see any fry. Could the pump be getting them? <<Could be getting some, Patty, but I think you might have more at work here than a fry-gobbling pump. Do you have water plants in your pond? Fry, if your Goldfish are, in fact, successfully spawning, would likely high-tail it for plants before they'd seek out the pots. Good thought, though.>> Should I feed my fish more often so they aren't tempted to eat fry? <<They'll be tempted regardless of an increase in food, Patty. Nature will take its course in that regard. A more viable option, if your intent on seeing more fish in your pond, would be to capture the fry, if/when you discover any, and raise them outside of the pond until they're large enough to go back in.>> One of the five seems more timid and smaller than the rest which are extremely aggressive. He/she actually uses the sunken pot to hide in. <<This will, hopefully, change with time and the fish's size, Patty. Goldfish aren't, by nature, aggressive fish but can certainly appear as such during spawning with the males nudging and bumping the females to encourage them to drop their eggs.>> In addition I have two resident frogs in my pond. Would they eat the fry? <<Depends on the flavor of frogs in the pond. Bullfrogs, for example, will go after fry/small fish but common, garden-variety frogs will be more content to eat insects than Goldfish fry.>> Cheers, Patty <<I wish you luck with finding new additions to your pond, Patty. Be patient and Im confident they'll show up. Best regards. Tom>>
Re: pond breeding or not
  7/4/07 Hi Tom, <<Hello again, Patty.>> Thank you very much for your speedy and thoughtful reply. <<Happy to do so, Patty.>> I'm actually leaving the blanket weed alone in one corner of the pond in hopes that fry will find it shelter. <<Excellent!>> I haven't seen any new faces (fins) yet, but the weather has been rather cool. This is my first summer with this pond and climate (came from France to England) so I've some learning about seasons and such to catch up on. <<Except for a stint in the Navy, Patty, I've spent my whole life in Michigan (USA) and haven't figured out the seasons here yet. (Neither has anyone else who lives here!) :) >> Thanks again, Patty <<You're more than welcome, Patty. Cheers. Tom>>

FISH FARMING (KOI) 06/27/07 Bob, I read your article on the net, about Koi & pond fish breeding. I have a 3/4 acre spring fed pond, My kids gave me 13 Koi for Christmas 3 yrs. ago. They are thriving, now we have about 70 beautiful Koi. They are all healthy & have Japanese markings/colors. Could you tell me where I can get info. on fish farming, how to get them out of the pond, about holding tanks etc... I'd like to start a small business. I would appreciate any info. you could give me, perhaps you know of someone that would be willing to "take me under their wing". I live in West Michigan-not far from Lake Mi. Thank-you! Sincerely, Harvey French <Mmm, well... there is a bunch to all this... from knowing the "blood lines" of the fish you have and will have (takes years), granting you an idea of what sorts of percentage varieties you'll likely produce... keeping the sexes separated, culling vigorously... To aspects of business... who will you sell to? How will you make delivery? To legal matters... some States are leery of Koi/Carp (the same species, Cyprinus carpio) getting loose... For a good general idea of what you're up to, take a read through your local library for the many books on Koi/Nishikigoi... "Living Jewels" is a fave... Bob Fenner>

Re: Shrimp/eating pattern, for goldfish, repro...  - 6/25/07 Neale... thanks again for your reply. I witnessed spawning for the first time this morning at 5:30am. At first I thought it was a shark feeding frenzy, then a murder taking place when finally realizing my pond critters were just following Mother Nature's rules. At least I know that Sparky is a girl. Don't know about the rest of them. Pond is now in a bad state of disarray. All I know is that if I were a girl fish... I would definitely keep my leg's crossed! hehehe All I see is murky water, water lily leaves shredded, floating Anacharis and other rooted pond plants floating, bent reeds. Don't really care, just hope all are okay. Even little Shrimp was taking part... the little devil... not too terribly bent for bada bing... obviously. After 4 hours they were all swimming around as if there had been no party... just looking at me thinking "what are you looking at... we didn't do anything!". <Hello Barbi! Goldfish spawning is indeed very vigorous. If the supposedly unwell fish is taking part in the "nuptials", then it's pretty reasonable to assume he's in OK health. Fish only tend to breed when they are healthy and happy. This is especially true with egg laying species.> Shrimp is swimming okay, but isn't quite able to grasp a mouthful of food as everyone else is. It's as if his tail can't quite propel him up enough and he ends up with only a single pellet... sometimes even missing that! I found a website... and you have to enter the entire thing to have it come up. I can't send you a pix of Shrimp 'cause I don't own a digital camera... and if I did I don't know how to use my scanner... really techno-challenged here. But on this site you can see how his tail goes to the side. He is white, pink and orange, however, the only difference. On page 9 of this document is the picture: www.nda.agric.za/docs/AAPS/Articles/Aqua/FishDiseasesandHealth/Koihusb.pdf - whew! <For some reason, this link doesn't work for me. I get the old "The page cannot be found" page.> What do you think about his eating ability. They really aren't too fond of lettuce, or apples. Grapes... sometimes, but not always. <In a pond, you have some latitude, because of algae and pondweed. So provided you have lots of these in the pond, don't worry too much about [a] the green side of their diet or [b] whether all the fish get enough to eat. Koi, like wild carp, will eat algae and pondweed when nothing "meaty" is on offer. It's good for them. So just make sure they have access to greens of some sort, but don't worry too much about precisely what they are.> I'd appreciate anymore insight you may have about this, Neale... I feel as if I've been run over by a steam roller... just feel frustrated. Good thing I am a very persevering woman!!! Regards, Barbi <Ah yes, the joy of keeping animals. You're obviously really concerned about Shrimp, and that's a good thing. But I can't really add anything useful to my analysis without actually seeing the patient. Maybe you can borrow someone's digital camera? In the meantime, see if you can hand feed him, or maybe divide up the food into two or more portions around the pond, so the fish split up. Shrimp will forage on the bottom, so scattering sinking food around the pond might help, by putting food where he can easily get some. The main thing is keep an eye on his condition, check he isn't losing weight, and just get a sense of whether he's basically happy or not. It sounds as if he's happy enough, giving he's spawning. Good luck! Neale.>

Babies... pond goldfish repro...    6/21/07  We live in Arkansas and have a small manmade pond in the back yard. We have 8 goldfish of various sizes and shapes which live in the pond year round. Holy cow!! Now we have 3 little blackish babies swimming around. Are we grandparents? Two of the older orange goldfish are quite large and I have no idea if they are male or female. If these are goldfish babies, will they change color? They're about an inch long. <Greetings. Baby goldfish are indeed not golden. They are brown/green in colour with a metallic sheen. Only as they mature do their colours become more golden. Some fish never change colour, so you end up with a fish that looks like a "wild" goldfish, or at least, what the goldfish's ancestors look like. I think those ones are pretty cool myself. Anyway, goldfish breed quite readily in a nice pond, so there is every chance you have babies in there. You might decide to bring them indoors to rear them in a decent sized tank if you were worried that frogs, water beetles, etc. might eat them. But otherwise enjoy. One thing: do check you aren't confusing a tadpole of a baby fish. I'm sure you aren't, but the two are very similar, and tadpoles are black. Tadpoles of course lack fins except the long wiggly tail, whereas goldfish babies have normal fish-like fins, so they are easy to tell apart. Cheers, Neale.>

Forced breeding, Koi repro.    5/22/07 Hya, <And you>          I have an ordinary garden pond with mixed breeds but mostly it is the koi I wish to find out about hand fertilisation and rearing of the young. i am not into injecting chemicals. Just pulling the eggs out at the right time, to prevent them from being eaten. <And the milt? Or just removing the fertilized eggs (very sticky) on purposeful spawning media?> If that means bringing them out by hand to prevent this, so be it. Can you suggest a good publication, that will take me through this procedure? Many thanks and anticipation on your response.    Yours    Chas <There are many good references to review for this subject... One fave (though it deals with another cool water species here: http://www.amazon.com/Goldfish-Breeding-Genetics-J-Smartt/dp/0793800900/ref=sr_1_16/105-3926385-0690000?ie=UTF8&s=books&qid=1179845150&sr=8-16 Bob Fenner>

Koi, Pond Fish Breeding  3/9/07 I read your article on the web, I have a 4 acre pond that I have stocked with Bass, large and small mouth and blue gills. I am contemplating farming fish and was wondering could I segregate my natural pond which is in NJ and farm Koi? What items do I need to know and learn about? <Mmm... sort of depends on which end of a/the scale you're focusing on... just breeding "some" koi (same species as the common carp) is very easy... Producing numbers of high-quality sell-able tategoi (speculative... small koi), takes years of delineating blood lines... selection...> Oxygen content, water temp alkalinity etc. . Do you have any suggestions on where I can learn more before I invest. <Yes... there are some "standard works" in print... and many folks that will offer their input... I encourage you to join a local "koi" club (if there's one about) and to subscribe to Koi Usa... see the AKCA, http://www.akca.org/ on line... and peruse their publications/listings in turn. Bob Fenner>

Koi, breeding - 02/11/2007 Hi Bob,   I am interested in breeding Koi and possibly selling them but was wondering if there are any state regulations in regards to doing so. <In some States, yes... as this is the same species as the common carp (Cyprinus carpio), an animal that can be real trouble in many settings... stirring up the bottom too much... among other things, interfering with the reproduction of desirable game fishes> I live in Michigan and I want to make sure that I do the correct thing and make sure if there are any licenses I need to obtain that I do so. <Do contact the local "Fish & Game" and ask of them...> I am looking at making this a hobby and doing so for fun. <Is indeed a vocation of tremendous potential here> I spent the better part of two years building my own pond and bought several Koi that have reproduced.  They are amazing fish.  Any information that you could provide would be greatly appreciated.  Thank you Bob and have a great weekend! <Much to state, relate... practices to adapt/adopt... I STRONGLY encourage you to visit some such facilities ahead of proceeding here... re pond design... practices in culling, feeding... And to do an "economic profile" of this question... the cost of electricity, water, land... the opportunity cost/use of your time... Much to consider. Bob Fenner> Green Goldfish?? Repro., culling  9/6/06 Good Morning Crew, <So far...>             I have a new 750+ Gallon pond (Since July 1st) in Southern Arizona with a barrel style bio filter (adding a second this fall) and UV filter and 1100 GPH Pump with the following adults:             4 Sarasa Comets             3 Shubunkins             1 Red Comet             1 Orange Fan Tail             3 Florida Flag Fish for Mosquito Control <Neat!> and about 40-50 babies of all colors (maybe more - They spawn all the time and I keep finding more little ones every day)             I know I'll have to cull out some of them but I don't want to get rid of some of the desirable colored ones.  Most of the babies that are 1" or bigger have developed their coloring (some red/white, some Shubunkin). They have even begun swimming out with the other adults in the open water. My question is that I have found several that are Silver on their bottom half and a Greenish color on the top half.  Is this a throwback to their wild days or will they develop another color as they grow? <A bit of both... might change, might not> What can I expect them to look like as adults? <Only time, experience can/will tell. Likely by the time/size they're 2-3 inches TL you'll be able to discern which are going to look like what (is this English?)> Thanks. BARRY <Welcome! Bob Fenner>

Question about sick pond goldfish... Mmm, and Pond Circ., Filtr., Maint.    8/7/06 Hi - I could not find the answer to my question on your web site and hope you can help.    <Will try>   We have a natural outside pond. It is under shade all day and has much foliage around it but none in it other than the occasional foliage which drops in from around the pond.  The pond measures aprox. 26 ft by 14 ft by 4 ft deep.  It is always clear and is fed from the runoff of our spring box. <How nice!> The water is constant circulating and has a pipe in the middle of the pond to control overflow. <Mmm, I would "sleeve" this... put a pipe over this one, notched at the bottom... to "force" "old water" and silt from the bottom rather than venting newer water from the surface>   There is a dirt bottom and a layer of leaves.  Also at the bottom is a very small spring which additionally feeds the pond. <Great>     I am not sure how old the pond is, we have lived here 5 years and it was here when we bought the home.  The only upkeep is the removal of leaves every 2 years or so.    The current gold fish we have in the pond have been there 3 years.  We originally had five. <No reproduction? Odd...> Just this past year, around the beginning of spring we lost one fish and now, recently, a second.    The goldfish both measured about 6 to 8 inches long.   Prior to dying, they both became lethargic and kept themselves close to the edge of the pond.  Resting themselves there and not swimming around at all.   They also lost many of their scales and where the scales were, there was "fuzz".      <Perhaps... secondary... decomposition>   We are worried there may be a disease or parasite in the pond. <Mmm, not likely... or at least not likely a primary cause/source of mortality here. Much more likely is some sort of environmental complaint... most easily addressed with the added "sleeve" over your standpipe mentioned above...>   We are also concerned that the problem may be at the source spring. <Mmm, yes... and/or some bit of decomposition in the "overburden"... the unconsolidated "ooze" at the bottom... again, best addressed with the sleeve, periodic increased (over)flow from rain...>   This is concerning because we use the water from this spring for our home use.  It is a separate spring box pumped to our home but the overflow from this spring feeds the pond.      <Mmm... Am sure you have particulate and chemical treatment to make this safe, potable... If it were me/mine, I would make use of a reverse osmosis device for potable uses... adding a "booster" pump for need pressure if required...>>   Any help you could give would be greatly appreciated.   Thank you.      J.M. <Welcome. Bob Fenner>
Re: Question about sick pond goldfish   8/8/06
Thanks Bob,   <Welcome>   Need clarification on the "sleeve".  I understand a pipe over the existing pipe but please explain the "notches" at the bottom and how it allows for water and material to be pulled from lower pond depth.      <Wish I knew how to make, post a drawing of such... imagine your existing overflow pipe... with a pipe of larger diameter placed over/around it. The new, larger pipe is "taller", and there are some holes, inverted "V" cut outs in this pipe at the bottom... such that, when the water level rises, the water from the bottom of the pond (about the cut outs) travels up, between the inner wall of the new pipe, the outer wall of the old standpipe... and to waste>   And again for clarity - the "sick fish" problem is likely environmental? <Almost assuredly> If so, then explain how the "sleeve" will "fix" this. <By improving the environment... helping vent "bad water" (nutrient laden, low/no oxygen...) from the system> Are we likely to lose the rest of our fish before the problem is resolved by the "sleeve"?      <Mmm, impossible to say. However, not worth trying to do something "overt" here... adding a large influx of water, "treatments"...>   I too was surprised that we have not had "babies" yet.   Any ideas on cause? <Many possibilities... mostly "environmental/water quality" probably... though could be predation... frogs, insect larvae (do you have Odonatans/Dragonflies?> Should we create "ambiance"? :) <Could... more diverse habitat would help... plants...>   Or,  there are babies but they get eaten.  Or there are eggs but environmentally the conditions are not right for maturity. <Some should survive>    Maybe I should stick to one problem at a time - the "sick fish" for now would be the priority.   If we lose the rest of our fish, is there a "stronger" fish we should consider for replacement? <Mmm, would need much more information... on where you're located, the local laws, the likelihood of the animals getting loose... too many issues to speculate on w/o much more input>      Again thanks for all info - and your quick reply.  JM <Bob Fenner>

Fall spawning of koi   8/7/06 Dear bob, John Butler here,  I have a 130,ooo earthen pond for starters, Three years ago my Koi spawned heavily, since then nothing. <Unusual... perhaps did spawn... the products consumed...> I live in the eastern panhandle of west Virginia . We have had very warm temps the last two winters. Could this be the reason why the koi haven't spawned ?   <No... not likely> Also can I get my koi to spawn in the fall? <Very likely yes> I have a large water source, will flooding the pond  with cool clear water at this time help the koi to spawn?   <Really... just likely need to add some spawning media...> also , WHAT DO YOU THINK WOULD BE THE SINGLE MOST IMPORTANT THING OR THINGS  I CAN DO TO GET THESE KOI TO SPAWN THIS  FALL . <No need to "shout" John. Please read here: http://wetwebmedia.com/PondSubWebIndex/pdfshbreeding.htm and the FAQs file linked above. Bob Fenner>

New Pond with Fry   8/2/06 Hi, <Hello there>             I have 8 goldfish in a 750 gallon outdoor pond (3 Shubunkins, 3 Sarasa, and 1 fantail (most are 4-5") and 1 large comet (7")) and have noticed several small fry in the water.  I have a few questions: 1.  I noticed the fry have been attracted to the lights in the bottom of the pond.  The larger ones keep sweeping in for the kill.  Should I leave the lights off till they are larger? <Mmm... best not to have lights inside biological ponds period... I would leave these/this off> 2.  If I remove the fry to raise, how big should they be before they can be placed back into the pond without fear of being eaten? <"Bigger than mouth-size" will do it. Goldfish (all the same species) are not cannibalistic per se... just ingest whatever...> 3.  What is the easiest way to harvest the fry from the pond? Take out all plants and adults and sweep with a fine net or what? <This is likely the best... use as large a net as you can handle of fine-enough mesh> Thanks for your help here. BARRY AUSTIN <Welcome. Bob Fenner>

Re: Breeding Fish  8/1/06 Just to let you know that you were quite right with saying the fry would most likely be the Rosies.  We seem to be getting a new batch every week and our pond is now absolutely heaving with fry of all sizes - I've never seen anything quite like it!!!  Do they have a season for breeding - i.e. when are they likely to stop? <Mmm, do reproduce all during the warming to warm months... Congrats again, and thanks for the update. Bob Fenner> Breeding Fish I have a pond with 6 blue Orfe and 10 rosy red minnows - so far they all get on OK! <Good... they should> I have noticed a large number of fry but do not know which have bred. <Likely the Rosies> It would seem most likely that it would be the minnows but I understood that rosy red minnow fry are golden in colour and these are transparent blue with a black line down the back.  Can you help? Deborah <Mmm... well, could be either... as the saying goes, "only time can/will tell". Congrats! Bob Fenner>

Will goldfish mating harm my female fish?    6/14/06 Hello, and thank you for such a wonderful website.  I Googled information about goldfish mating behavior and came across your site. <Thank you for this info.>   After reading many of the FAQs regarding mating/spawning behavior, I feel I still need to ask for more help and information. <Okay> Here's the situation:  I have a small (50 gallon) outdoor natural pond. It's very healthy, with lots of plants and snails.  A few years ago I bought 3 comets and 1 Shubunkin (Manny, Moe, Jack, and Vinnie), who have grown and thrived.  They are now about 3 inches long.  Late last summer my dear mother passed away quite unexpectedly.  She had several pets, including an extremely large feeder goldfish named Bubbles whom she kept in a barrel pond outdoors.  We immediately brought Bubbles home and put "him" into the pond, where "he" was just as a happy as a clam.  Bubbles is about 6-7 inches long, and just huge.   Today I began to notice extreme spawning behavior amongst the fish, and now realize Bubbles is a "she."  The other 4 fish in the pond are relentlessly pursuing her, even though she's a whale compared to them.  (I don't know Bubbles' age, but she's at least 4 years old.) <Yes... seasonal... the "hots" for sure> I'm very concerned about Bubbles in that I'm afraid the other 4 fish will just wear her out. <You are right to be concerned here. In this too small volume there is too likely to be damage... Need separating, pronto>   I don't want to lose her. Not for a long time (in fish years) yet.  She's such a memory of my mom that it would just break my heart if something happened to her that I could've prevented.  The problem is, I don't know where to put Bubbles (if I remove her from the main pond, which is covered) to keep her safe (I'd have to devise a covered situation because we have raccoon attacks). <Good> I also don't know how long she'd have to be away from the main pond if I DID remove her.  How long does this mating behavior go on?   <During most all warm/er months... Spring... Summer into Fall...> If it's just a day or two, can the female deal with it? <Mmm, possibly... but I would not risk this in the size system you have, the number of fish...>   Another problem is that I'll be leaving on a two and a half week vacation starting in early July.  I have someone house-sitting, and so taking care of the pond, but.???   What would you do?!   <Mmm, keep the female separated... change out some water from the pond into the container where "Bubbles" resides, hide the food... more potential trouble from feeding during your holiday than it's worth feeding> Thanks VERY very much. Annette in Washington   <Bob Fenner in S. Cal.>
Re: Will goldfish mating harm my female fish?  06/14/2006
Hi Bob, and thanks for your speedy response! I just realized I erred in the size of my pond.  It's actually 100 gallons.  Do you think this makes a difference? <Some... but still too small for what all is going on here> If not, then Bubbles will have to live in a small barrel pond for the duration of the summer! <Mmm, do keep an eye on this container as well as situating it near the house to curtail large/r swings in temperature, water quality. You might want to add a air-driven sponge filter... Tetra's Luft pumps are great for this application, as well as their "Billi" filters or Jungle Products brand...> Again, thank you! Annette <Welcome. Bob Fenner>

Pond goldfish babies   6/1/06 We have a pond in our back yard, (Savannah, Ga) approx. 1500 gallons with 2 waterfalls and 2 filters systems 1 Koi and 5 adult goldfish, 1 goldfish about 1yr old (baby from last year). After trying for three years to get the pond established we have finally were able to get thing going. This year we have found 75 to 100 baby fish, various sizes (1/2 in to 2 ins.) along with a lot of tadpoles.  We have lots of plants for the babies to hide. How many fish can we have in the pond? <Mmm, about this many (not holding up hands)... will need to be thinned out as they grow> Do we have to remove some of the babies and if so what do we do with them? <Trade, give them away... Craig's List, fish stores...> Any help will be greatly appreciated.  We love the pond. It is a great place to relax and the children love to watch and learn the circle of life within the pond. Irene <Ahh, good. Bob Fenner>

Butterfly Koi repro. mostly   5/21/06 Hi, Bob et al.    <Leigh>   My husband and I have a large outdoor pond with 11 Butterfly Koi (2 to 5 years-10" to 15") down here in Texas. Queenie and George (I couldn't tell males from females when naming them) spawned this year, and yesterday we noticed several (about seven or eight) babies. They're only about 1 1/2" long. I'm worried that the big ones will eat the little ones. Is this a possibility? <Very unlikely. Koi/Carp don't eat their young, or small fishes... unless very small, incidental> I bought a little mesh cage to move the little ones into to get them away from the 11, but the pond is too big and they are too fast. Should I just accept the inevitable, or is there hope that these babies will not end up as breakfast? <These will likely not be eaten... will develop, grow here> I have finally come to grips with the fact that the adults ate most of the eggs...    <Yes, this is common>   Also, are there varieties of Butterfly Koi? <There are a few varieties/types, though they are all the same species (Cyprinus carpio), as are all "regular-finned" Nishikigoi/koi> Ours have very long, flowing silky fins and tails, and don't really resemble the pictures of Butterfly Koi on your site. Could we have something other than Butterfly?      Thanks!   Leigh from Houston <Mmmm, yours are probably just a bit older, nicer... Bob Fenner>

Winter Goldfish Spawn  - 03/27/06 Hello, Could you please tell me the minimum temperature at which goldfish fry (about 1,500 - 2,000 and 3 weeks old!) can survive outdoors'? I want to release them into my pond (Ohio, late March) and need to know when I can safely do this. These fry are the spawn of (former) feeder goldfish which I took on as "temporary winter adoptees" for a friend until their forever home pond was rebuilt this Spring. Well, I took too good care of them (Just kidding, I know there is no such thing!) and, surprise, they spawned! Now I am now overcome by goldfish! Having extensive experience spawning African Cichlids years ago, I know enough about keeping parents and babies all healthy and happy indoors - but it's time they moved on...and out! Thank you, Kathleen <Well goldfish are really carp which live wild in your area. But you do not want to shock them. I would allow their tank to cool down as much as possible by removing any heater and, if possible, keeping the room cool. When the pond and tank temps get close you can release the fry. I would also check the pH of both, a big swing can kill. Good job getting such a large spawn, but this really is far too many fish for a pond. You would need an unstocked lake. I suggest you keep a few with the nicest colors or patterns and selling the rest as feeders to a LFS. Please do not release them into a lake or river. Fish kept in a closed system may carry bacteria that wild fish can not cope with. Don>   

Pond goldfish ... reproduction?   1/30/06 Hi crew, Just a few question that i hope you can help us with. <Will try> We have 7 goldfish and 3 koi carp in our pond which has a filter to it. The pond is very large and we believe is very sufficient in size and depth for our fish. <Numbers please> One of the goldfish seems to be pregnant and so a lot larger than the rest. Is there anyway we can tell?   <Mmm, not practically... there are other "conditions" that look like this... but blockage, fatty infiltration... Should not be egg-bound during cold weather/season though...> How can we tell if they are eggs or  not? Also what do we do, as i know that if we leave the eggs in the pond the  goldfish and Koi will eat them. <Posted... please see WWM re> What kind of plants do we need for the pond, and how many.  The size of  the pond is 9ft x 7ft x 3 in depth. Hope you can help. <Also posted> Thanks Heidi and Nigel. <Bob Fenner>

Breeding Pond Fish - 12/26/05 Hi, <<Hello>> First of all thank you for your great site, I have found it very useful. <<Excellent to hear.>> I have a question which I am not sure if it's covered specifically on the site. <<Mmm, probably...most are.  But go ahead...>> I've got a well established outdoor pond with a number of goldfish in it. <<Me too>> Recently I noticed one of the fish chasing another all day until both are exhausted.  I thought they could be playing or fighting but another explanation is they might be trying to breed?? <<Possibly>> Thus I came online to research a bit more about how goldfish breed.  I was concerned to read among other things goldfish like to eat their own eggs and you need to separate them from the eggs once they are fertilized. <<Not necessary/desirable for "casual pond use" in my opinion...a few of the eggs usually survive the parents, the bigger threat is probably insect larvae.>> With a pond of this size and depth and with rocks, plants etc., it's impossible to tell when or if they have laid eggs. <<Agreed>> My question to you is then is there no chance of them successfully breeding as the situation currently stands? <<Sure!  I have several generations of goldfish (Comets) in my pond that have bred/propagated without any outside interference from me.>> Is using breeding mops the only way? <<Nope...but pond plants like Anacharis, Parrot's Feather, and lilies will help.>> My subsidiary question is then, in nature surely no one separates the eggs and the fish, <<True>> so why can't the natural cycle happen in my pond, <<It can>> why do I need to use artificial means like the mops to allow breeding? <<You don't>> By the way, I am not trying to breed new goldfish, but it will be a nice to have if it happens, <<It will happen>> if there are eggs in the pond I prefer them not to be eaten by their parents!! <<Not something you can prevent...but then you wouldn't want "every egg produced" to grow to maturity anyway.>> Thanks for your help!  I look forward to your reply. David. <<Regards, EricR>>

Market Size for Koi 12/2/05 Hi there!! <<Greetings!>> I'm from South Africa, currently doing market research for Koi. Could anyone PLEASE give me any estimate for the market size for Koi? Kind regards, Ane <<Well, as they are colored and/or coloring up, best salable, usually at around 3"-4" (7.5cm - 10.5cm)) in total length, though I have seen them offered as small as 2". I've not seen koi actually ON the market at smaller sizes, but have been involved in a small breeding/rearing operation. Marina>> 
Market Size for Koi - II  12/5/05
Hi there! <<Hello again, Ane.>> Thank you for replying.  <<You're very welcome.>> What I meant, was the production/industry size for Koi. Kind regards Ane <<Did my previous reply give you the answer you sought? The question just seems to be re-phrased, ultimately meaning the same thing as I understand you - at what size can koi be "market-ready" or "salable", yes? Marina>> <Most small koi are sold at more than three inches total length... four is most common and easiest to ship with low mortality, generally sold in two inch increasing increments beyond that. RMF>

Large-ish man-made pond in NY state 10/10/05 Dear Mr.. Fenner, Twenty years ago I had a bulldozer enlarge a small spring into a clay-bottom, spring-fed pond 80 feet by 40 feet by 10-12 feet deep. Had millions of tadpoles. Then, I was offered a bucket of bull-heads and said fine and so the fish end of the spectrum arrived. Fifteen years later, I bought a couple of dozen mixed goldfish and koi.  I wasn't yet at the collectible stage, just wanted fish. Currently, I have a wide mixture of mutt-fish -- (I adore them,) lots of orange goldfish, some with white markings, six identifiable koi, one gray/blue, one calico with long fins, one gold, and a couple of "ghost koi" or so-called "ugly koi" and they are ugly! I also have a long yellow goldfish about two feet long. I'm thinking he has to be a goldfish because he doesn't have the barbels that koi are supposed to have... am I right? <Possibly, or could be a cross> I also have a couple dozen colorless/gray fish with no barbels that have joined the herd. I'm thinking these are koi/goldfish crosses?  I feed my fish in the evening, about a quart of dry pond fish food. use better grade stuff with wheat germ early in spring and late fall until the water temp. drops.  The pond freezes over in the winter, but the spring trickles through and out through a drain over the berm. Earlier in the life of this pond, I used to have plates of foamy green algae in the summer. Now I have none. I have no tadpoles that I can see, but I still have frogs and would like to keep them; worry that fish are eating frog eggs.  I have lots and lots of baby orange goldfish, some with black dorsal fins - shark-like -- what are these? <"throwbacks"... a percentage of fish that are "wild-colored"> I have lots and lots of bull-head catfish who come to the surface to feed with the fancy fish. (who knows, I may have giant bullheads on the bottom.)  I also have your basic apex predators: a blue heron -- <A factor in the preservation of more throwbacks over fancy coloreds> I chase him by barking like a dog and trying to run him over with my station wagon.  At least one snapping turtle. I throw him a dead chicken (rotisserie type) every couple of weeks. THE Question, at last -- have you any suggestions for overall pond health and koi increase for this pond? <Mmm, you could add an aerator, some live plants> Thanks for your excellent articles and your willingness to tutor fish lovers like me. <Please use your spelling, grammar checker/s... Bob Fenner> Maxine Paetro, Amenia, New York 

Too many Pondfish  10/6/05 We inherited our pond last year when we moved into our new home.  The pond is kidney shaped, about 7 ft. long X 4 ft. wide and about 3 ft. deep.  I think we have WAY too many fish in there.  They don't seem to ever die, (at least there haven't been any floaters), but there must be at least 30 fish in there of varying sizes.  They seem to be fine in the winter (we live in Southern Ontario and keep the water moving with a pump and chop a hole every day so it doesn't completely freeze). <Chopping is very dangerous... Please read here: http://wetwebmedia.com/PondSubWebIndex/pdmaintwint.htm and the linked files above> Last year I think they all survived and this spring there were a lot more babies.  We'd like to get rid of some of them, but we have no idea what to do with them.  We live near the Great Lakes, but I'm sure I can't just throw some into the lake. <No... do not release anything into the wild>   What do you suggest we do, if anything. Thanks Deedee Hammond <Contact local fish stores, garden centers that sell pond livestock... they will likely buy your excess livestock. Bob Fenner> Birth process, small koi 8/23/05 One of my 3-4" koi (purchased about a month ago for my pond) appeared to be pregnant. <Mmm, appears... but is too small to be "gravid"... too immature to develop eggs> Saturday I happened to see her expel what looked like a 3-4" orange strand (looked like thin roping). She trailed it behind her for a minute or so, then swam into a clump of water hyacinth roots and came out without it. I've read about fish eggs, but I haven't found anything that sounded similar. She appeared to be much less bulky this morning. I'm new to all this and have no idea what's going on. I found your Website and thought I'd ask. Can you explain? And where would I look for your answer? <Mmm, is likely just some sort of gut blockage that was relieved...> Sorry to be so clueless - I've been thrown into pond fish ownership and what I think is motherhood before I've had a chance to figure anything out! Thank you! <No worries. There is a bunch to this (pond keeping)... and thankfully many good folks to seek input from. Cheers, Bob Fenner>

Re: Birth process 8/23/05 Bob, thank you so much for your immediate reply. I'm not sure whether I'm relieved (not ready yet for the responsibility of motherhood) or disappointed (my fish is constipated!). But your answer has spared me from spending after-work daylight hours  on my knees staring at hyacinth roots. Cheers! <Heee! Have spent actually weeks of my life staring at (while extracting) said Eichornia... Excelsior! Bob Fenner>

Shubunkins in a pond, reproducing... a Hemingway start 8/19/05 Morning Bob: We have a pond approx. 300 ft long, 60 ft wide and 20 ft deep. Soil in this area is just pure mud so the pond is always very murky and does not have much movement. We keep it stocked with rainbow trout. Four years ago we put two Shubunkins about two inches long in it and, of course, they immediately disappeared. Imagine our surprise a couple months later to find two large, beautifully coloured fish in our pond! We did not think we would see them after our cold Canadian winter but, come spring, there they were and have been year after year. This summer has been extremely hot which, I understand from your page, can cause them to breed.   <Yes...> A few days ago we went out to 'feed the fish' and were absolutely amazed to see baby fish feeding. All over the pond we saw little swirls and in each swirl would be about 15 - 20 little fish.  Question is, will they survive in the pond, which is covered with ice and snow for 4 - 5 months, over the winter? <Likely so> I shudder to think what my pond will look like if they all survive and breed! Horrors! Ida-Mae Kennett Ontario, Canada <You might want to "thin the herd" during the warmer months... a large net, selling some to local stores... Bob Fenner>

Pond goldfish 8/7/05 We have an established pond with a small trickle feature to keep the water moving, one of the gold fish has developed what look like blisters or ulcers on top of its head. They are about 1-1.5mm across and do not appear to be irritating it nor do any of the other fish have them. Any ideas please? <Ah, yes... these are very likely what are called "pre-nuptial tubercles"... males get such bumps on their heads this time of year> we have separated it but it has had to go into a small tank so we don't want to leave it there too long. Cheers <No worries. Please see these files: http://www.google.com/custom?hl=en&ie=UTF-8&cof=BGC:%23FFFFFF%3BT:%23000000%3BLC:%230000CC%3BVLC:%230000CC%3BALC:%230000CC%3BGALT:%23008000%3BGFNT:%23000000%3BGIMP:%23000000%3BDIV:%230000CC%3BLBGC:%23FFFFFF%3B&sitesearch=wetwebmedia.com&q=pre-nuptial+tubercles&spell=1 Bob Fenner>

Pondfish repro. behavior 8/6/05 Hello, I was wandering if you could help me with a fish problem, you see we have about 30 fish in our outdoor pond, and we have noticed that about 6 of our fish is bullying one of our new fish (given to us by a friend), they were pushing him (or her) to the sides of the pond and to the top of the water, we thought it would be best to separate him from the rest of the group, so be put him in a bucket, he is worn out and is not swimming. I want to know if we should let him back in the pond? I also want to know why they are beating him up and what shall we do if they do it again? Thanks a lot, C <Likely reproductive behavior. Best to place the new fish in another system for a few weeks. Bob Fenner> Pondfish repro. 8/6/05 Hey, I've had fish as long as I can remember, in aquariums, however now I have a pond. All my other fish have given birth to live young or have been impregnated before they dropped the eggs. But as I understand koi and goldfish females lay unfertilized eggs and then the males fertilize them? I have a female koi that I think (thought) is pregnant and was thinking of moving her into a smaller tank to save all the baby fish. but now apparently I should leave her in the pond or else I won't get babies? thanks PJ <Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pdfshbreeding.htm and the linked files above. Bob Fenner>

Goldfish/koi separating from their babies 7/30/05 We have a pond in our backyard with about 12 adult goldfish/koi. Someone recently had babies I counted about 16 of them). Anyhow my husband tried to get all the babies to put in a tank inside our home so he doesn't over populate the pond. Well, he only could catch 3 (Boy are they quick). This is gonna sound strange but I swear the mother of those babies is looking for them. Am I going nuts or what? <Mmm, can't make such a judgment... but these fishes don't exhibit parental care> Today I found 2 of the goldfish almost guarding the babies. He wants to take the other ones out tomorrow and I don't want him to take them because of the way the fish is acting(? mother). He says he doing the right thing but I literally was crying today because I was outside just watching this goldfish do this. I don't know if its just me being a mother or what. My neighbor officially thinks I'm nuts because I'm outside crying that he's gonna do this tomorrow. Please help.. Thanks, Jackie <Please do not be concerned re the movement of these young... or leaving them with the adults... all should be fine either way. Koi and goldfish don't eat their young (unless they're very small), nor do they "mother" them. Bob Fenner>

Scottish Koi, caring for young 7/28/05 HI There <Hello> I am writing to you from Central Scotland from a small village which is fairly high and often fairly cold as we are 1000 ft above sea level. <I see> My husband and myself built a small pond approx. 16 years ago when we also introduced a selection of pond fish including Koi Carp, Goldfish, Comets and Shebumpkins (pardon the spelling if this is not correct !!!).   <No worries, likely Shubunkins> These were   all introduced when fairly small and over the years we have lost a number for different reasons but we still have approx. 13 mixed fish of which we have 5 fairly large Koi Carp (approx. 16" in length). Over the years we have changed the pond in size and periodically cleared it.  We have a filter and a UV light to help. When we were recently  clearing our pond as in the previous year our  filter was damaged due to excessive frost and the pond became very murky and in  need of clearing before we purchased a new filter.    Whilst we  have never conscientiously tried to breed our fish, to our surprise, we found 3  to 4 small fish which gave us pure delight. <Ahh> We are curious to know how old these fish might be and whether or not we should be doing anything to ensure their continued growth, and whether or not they are in danger from the existing fish ? <No worries re the other fish... likely these fish came from last years spawning> I would say these fish are approx 1" to 2" long and since clearing the  pond they seem to keep themselves mainly under the lily leaves.  To my  surprise however they do eventually venture out in a group and at feeding time  have been seen appearing and nibbling at the usual fish stick which we  feed the rest of the fish on. We would appreciate any advice you may have to give us regarding our new babies. <Not much to do... as the food, if too large, will ultimately feed them by supplying nutrient to algae, insects...> We found your article very interesting indeed and look forward to hearing from you. Isabel and Peter Gray. <Good to make your acquaintance. Bob Fenner>

Koi flipping over 6/29/05 I read an entry in your koi diseases section from a person called Lorenzo (page 57) and it sounds like a problem my fish starting having yesterday.  Three days ago my husband changed the water in our pond and took out about half of the rocks that were ornamentally placed around it.  (he removed the rocks because they had thick algae on them).  Ever since then, the fish have been racing around the pond, sometimes chasing each other and flipping and jumping.  I am very concerned and would like to know if this sounds like a disease problem or an environmental problem? Very worried! Denise <Mmm, could be that the water change, loss of cover (the rocks) is over-stressing your fish, but much more likely the temperature and water quality change has triggered a reproductive frenzy here. I'd keep your eyes on your aquatic charges for evidence here, and possibly the need to separate, maybe treat them for scratches from being too rambunctious. Bob Fenner>

Too many babies! Lots of small koi in a big pond I have a large pond, 25 x 30.  My 14 koi and goldfish spawned and now I have about 100 babies, at least the ones I can see.  I need to get the babies out of the pond.  Is there a way to do it other than sitting idly with a net?  Thanks for your help.  Joan <A larger net... swept across the basin, two plus people... Bob Fenner>

Koi pregnancy Hi Robert, <Joyce> We have a 9 x12, 4 deep pond in our backyard for a few years. The koi are about 18 long. Recently, one of the koi' belly is bulging out noticeably, I suspect it might be pregnant. <Maybe...> The temp has been ranging 25-30 Celsius, with night low of 14 Celsius.  How long will it take for the eggs to be matured and be spawned? <Please read here: http://wetwebmedia.com/PondSubWebIndex/pdfshbreeding.htm and the linked files above> Please advise so I can start watching out for eggs and babies. I want to take good care of them so they won't be eaten by others before they get a chance to grow. Oh yeah,  we also have many huge pond fish, fan-tailed goldfish too, I hope they will leave the eggs alone if there's going to be any. Thanks for your advise in advance. <Study my friend. Bob Fenner>

See-through Koi/Goldfish Fry Dear Crew,      In my pond I have a variety of goldfish, comets and koi which are all of different sizes. Earlier this year I noticed a number of new fish of about 4cm in length. Some of these new fish are white, some are orange and others are plain brown. Would I be right to presume that the plain brown ones are goldfish and the others are koi? <Mmm, not necessarily... there are brown ("throw-backs") of both> Also more recently some of the white ones have developed orange spots on their heads while others seem to have gone almost see-through! Are these fish OK? Thanks for your help Chris, in the UK <Very likely nothing "wrong" health-wise with these transparent-head fish, but they are largely culled... undesirable for this characteristic... Take a look at "grand champion" koi and valuable goldfish... their heads are color-saturated as the rest of their bodies. If you enjoy them though... Bob Fenner>

Breeding koi I have twenty plus koi in a large- 100,000 gallon- pond the fish are 10 inches to eighteen inches. They the have only been in the pond for six months. In one corner of the pond there is a shallower area separated by a dry stone wall. My Question is; could this smaller area be useful for breeding. <Mmm, yes... a good spot to place some suitable media... you can remove or "fence off" for later development> the small pond is two feet deep and contains about a thousand gallons, with the water being free between the dry wall. To date there is no sign of breeding. I live in NSW Australia and we are now starting our winter. Our coldest temp would be 2c and our hottest 36c <Somewhere near the rising temperature, the high 20's C., you should see evidence of spawning behavior. Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pdfshbreeding.htm and the linked files above. Bob Fenner who apologizes for the tardiness in this reply>

Pond goldfish help! I have spent a lot of time in your website and cannot find a VERY SIMPLE answer. I have a natural pond and have added goldfish along with a filter system, plants, etc. The pond is well established with plants and plenty of natural food for the fish to survive on (algae, etc.). We have a goldfish who laid her eggs two weeks ago and we haven't seen any sign of babies yet. How long does it take the eggs to turn into visible fish?  <Depending on temperature, they hatch out in 3-4 days... but are very small... May have been consumed...> I've heard that mothers will eat their babies. True? <Not usually with goldfish> Will there be more spawning and eggs this summer? <Yes, likely> We are in Savannah, GA. Thank you very much. Suzanne M. PS Wonderful website! <Thank you, Bob Fenner>

Breeding Koi - And (Not) Using WWM Hi my name is Don and I would like to know if I should increase the water temp of my pond would this encourage the Koi to breed? And if so what temp is best? <<Hello, koi, goldfishes, and others are indeed induced to breed with a rise in temperatures. However, if housed in an outdoor pond, the increases found with spring's coming should be enough, assuming the fish are sexually mature. Also, please, make good use of our site, this question and others have been answered in the past, a simple Google search using "breeding koi" has netted me the following: http://www.google.com/custom?q=breeding+koi&sa=Google+Search&sitesearch=wetwebmedia.com  And more specific to pondfishes: http://www.wetwebmedia.com/PondSubWebIndex/pdfshbreeding.htm. Marina>> 

Pregnant koi? How can you tell if a Koi fish is going to have babies?  My mother has a fish and she thinks it's going to have baby, it is huge she looks like she's going to blow.  Can you help me please? Angy Watson <Mmm, could "just be fat", depending on the types, amounts of food it's been fed... or have some sort of gut blockage... depending on water quality and the food issue... or a disease condition... Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pdfshdisart.htm and the linked files above... Bob Fenner>

Stripping Goldfish hi, <Hi, MikeD here>   Thanks for the info regarding "goldfish attack" I now have one set of eggs that I collected from the pond using the mop method. I am now interested in hand spawning as I have read this is more successful than natural spawning, but I cant find any good information on how to do it, I don't want to hurt the fish, so I'm reluctant to try it with out proper advice.<My suggestion is to try and find someone who is well versed in the procedure or do a search on "stripping" the roe and milt and read VERY carefully.  I've been in the hobby for over 40 years and wouldn't try it myself as the odds of injury are simply too great. Often the fish are injected with hormones in commercial applications as well.> thanks again, Sheridan South Australia

Frozen Fish Fry?       I have a goldfish/Koi fry question. It is now mid-September here in Connecticut and we have a new hatching of fry. My question is, should I pull them for the winter, or are they likely hardy enough to take the cold even though they are only about a week old? <I would bring these fry in as soon as they are an inch or more in length... before the first frost if possible> Also, If I have plenty of floating plant variety, is there a significant chance that they will be consumed by the adults in my 1000-gallon pond? <Not usually consumed by larger, adult fish period. Bob Fenner>

"Pregnant" Koi Hi, I don't know if this is where I'm supposed to send questions, but I could use some advice.  My family has a pond/waterfall built into our screen porch.  At the moment, we have 8 Koi and 1 red eared slider (turtle).  We have noticed that one of the Koi has a large belly.  All of our Koi eat about the same amount so I don't think it is obesity.  We believe she is carrying eggs. <Likely so>   If this is the case, are there any special things we should do? <Probably not... if the rest of conditions are favorable (mainly water temp., presence of males) she will spawn, if not, in almost all cases the eggs will be resorbed... There are occasions, instances of "egg-blockage", but in actuality these are rare> Will the male Koi sense that she is ready to spawn and interact with her?   <Oh yes... likely after a day or two of a warming trend in the weather> Will the turtle and or the adult Koi try to eat the fry? <Not the Koi, but the turtle may when they are a bit larger... not as eggs, fertilized or no, and young/fry are quite quick...> Also, I have read that I should put a rope or something in the pond for her to attach her eggs to.  Is that something that I should actually do? <You can... the eggs will be broadcast, and are sticky... so they will adhere to most anything, including the pond sides otherwise. Floating plants like Hyacinths, Water Lettuce are good here as well.> We are a bit ignorant as to the special care of the Koi.  We know how to feed them, keep them healthy, and clean the pond, but we were told it is rare for them to breed in captivity so we didn't really worry about that aspect of their care.  Any help you can give me will be greatly appreciated.  If you could reply to my e-mail address XXXX.com that would be very helpful.  Thank you. Jaime Leap <A new experience awaits you, enjoy and learn by it. Bob Fenner>
Re: "Pregnant" Koi
Dear Mr. Fenner, Thank you for your advice.  It will come in very useful.  After I sent my e-mail yesterday, we found that the fish in question is missed quite a lot of scales.  I later found that scale loss can be associated with spawning. <Yes, during "racing bouts" the fish and male cohorts can be quite rambunctious, dashing about, hitting the edges of the pond... maybe even launching themselves out!> However, this morning while I was feeding them, my turtle snapped at her side.  We didn't know whether this was just a coincidence and she was just in the wrong place at the wrong time or if she was starting to smell like food to him.  Part of me thinks that it was the former reason.  But just for safety's sake, we placed her in a bucket with water from the pond.  This is a solution for right now, but the bucket doesn't have a pump, and the water will become depleted of oxygen eventually.  What do you think we should do?  Thank you very much. Jaime Leap   <I would move the turtle instead, and leave the fish (all of them likely) in the pond. Bob Fenner>

Questions re Koi fry Hi Mr. Fenner I was wondering if you could answer some of my questions. We have a pond outside with 4 Koi and one goldfish. I have caught over 20 babies about 1" long and will raise them inside in the winter. 5 of them are golden and the rest of them looked black from the top view when I caught them. They have been in the house for about two weeks now. The golden ones have kept their color, the black ones are still dark on the top but have really lightened up to a silver and some are almost white on the sides. <Okay> Is this normal for Koi fry? <Not atypical... many do not change color, or even show much, and are discarded by commercial breeders (culling)> I am currently setting up a 46 gallon bowfront in which I will transfer the fry into in a couple of days. Will these fish likely keep changing their colors? What other surprises should I watch out for? <Could or not... only time can tell. Should "set" in terms of color and pattern at about four inches, 10 centimeters long or so> Thank you very much for your time. I really appreciate any help you can give me. D.B. <Happy to share. Bob Fenner>

Are you the same Bob Fenner? Pond fish young Was reading a web page where the discussion was breeding of Koi, goldfish, etc.  I tried to find how to post a message there, but could find no link.  I'll throw out the question, and if you are not him please disregard....I built a waterfall/stream/pond in my back yard this spring (late may).  I bought 4 fancy goldfish from a pet store and introduced them, about a week after installing several tropical lily plants.  The goldfish are about 5-6 inches long.  In July I suddenly had 50-75 babies swimming everywhere (hard to count because they like the rocks).  Here's the question.  The goldfish are all almost identical with white and gold markings only.  The babies have black spots, gold, white, and a reddish color.  Do you think the goldfish had babies in a month or did I buy tropical lilies with Koi eggs on them? <Good question, possibility... much more likely the goldfish reproduced, but it may well be that you have some "recruits"... on/with the lilies> It seemed to happen awfully fast and the babies are much better marked than the goldfish. <This happens at times... and they will likely change their color, markings with time, growth> I'm just wondering what kind of babies I have, and all the black spots are throwing off the goldfish baby theory.  They are growing fast and doing quite well, just wish I knew what they were and where  they came from. Thanks for you help! Brian Dryer <You'll soon know... when the young are a few inches long they are easily distinguishable. Bob Fenner>

Reproducing pond goldfish Dear Bob I have 4 goldfish in an outdoor pond.  A couple of months ago one or some of them laid eggs.  I have no idea as to the gender of the fish. But I have many water hyacinths.  My fattest goldfish and sometimes my second biggest spend a lot of time laying between the roots of the largest plant, fanning.  They are healthy, energetic and they eat well.  Could they be caring for eggs?  They were in someone else's pond for years, and reproduced there, he thinks they may take care of the eggs.  Can you tell me what's happening?  Sincerely, < Goldfish really don't care for their eggs like cichlids or some other fish do. They mainly scatter them around over rocks or plants and let nature take its course. -Chuck> Lisa S.

Koi spawning, doitsu scalature Dear WWM, John here. Well my Koi spawned this spring and everything looks great, but there are some Koi that only have scales at the dorsal fin and scales that follow the lateral line, can you tell me what variety of Koi this is. Thanks for you time john. ps these scales are large. <This type of scalature is most often called "Doitsu"... a bit of a vulgarization, way of the Japanese saying "Deutsch", as this type of large scale pattern is also often called "German", "mirror scale"... the naturally occurring trend to fewer, larger scales is an advantage in growing food carp (the Koi is the same species as the common carp, Cyprinus carpio) in that it's easier to de-scale preparatory to cooking... All the varieties of Koi otherwise (Kohaku, San Showa...) can have this type of scaling... and it appears that some fish in your breeding mix have this genetic heritage to pass on. Bob Fenner>

What are these new fish? I've got 1 large 3 year old goldfish (8-9 inches long) and 2-3 Shubunkins (about 4-5 inches long) and 1 fish that may be a koi (has barbells) and another that I can't see barbells on but looks more koi-like.  I have many new fish now ranging in size from 1/4 to 1.5 inches...they are silvery brown...and then I have the occasional 1/4-1/2 inch baby that looks like it is multicolored already...VERY different looking.   Are they born multicolored and then change to the silver/brown...before eventually getting their adult coloring? <Sometimes, yes> I'm fairly certain the Shubunkins are the culprits here...a few of them were getting pretty plump around the middle...but seems odd that the occasional fish is NOT the silver brown color.  Also could the small Shubunkins have crossed with my big old goldfish? <Yes... like domestic dogs, all goldfish are of the same species... and to add to the confusion, koi (Cyprinus carpio) can crossbreed with goldfish> Does size/age matter to these fish? <Only to the extent that the parents are sexually mature... for goldfish, about six months; for koi a year or so> Thanks for any answers (I did look on the site and follow the suggested links...hope I haven't asked for repeat information. Jill <Thank you for writing, and congratulations on your new fish. Bob Fenner>

Koi Genetics Question - 08/22/2004 Hello WetWeb- <Hello.> My question is if you breed a standard koi with a butterfly koi, will you get either or, or a combination of the two? <To be honest, I'm not quite certain of the genetics involved, here....  *Assuming* that the butterfly fin trait is recessive, and that the standard fin trait is dominant, and that your standard fin fish is homozygous for that trait, all the fish from this cross will have standard fins, .  If the standard finned fish were heterozygous (dominant trait exhibited, but carries the recessive trait), 50% of the fish will be heterozygous (exhibit the dominant trait, carry the recessive) or homozygous for the recessive butterfly-finned trait.  Again, this is all only true if standard fins are dominant, butterfly fins are recessive, and there are no other factors at play - I do *not* know if this is so.  I would recommend taking a look at koi genetics books - I know I've seen a couple in local book stores.> Thank you. <You bet.  Wishing you well,  -Sabrina>

Re: Breeding Koi: Butterfly with standards Hello WetWeb-My question is if you breed a standard koi with a butterfly koi, will you get either or, or a combination of the two. Thank you <Hi there,  It's really hard to say with any degree of certainty, you can make an educated guess if you knew what the parents of each of these fish were like.  But, sadly, when you breed them you will probably have to just see what happens.  When we bred our Koi, the offspring would always be sort of a mixed bag.  Some having distinct traits of one parent, while others seemed to have traits from both.  Or sometimes you have them that they look like neither.    My opinion is if you bred a standard with a butterfly you will most likely have less than a third of them come out with the butterfly fins.  Best of luck with the koi and your breeding attempts with them. -Magnus>

Koi growing time We have just had about 12 baby Koi/goldfish.  They are blackish/grey in color now and I understand they will show color eventually.   Approximately, how long does this process take?  We live in Connecticut and the temp. in August is about 80 degrees on average. Thank you Nance <Factoring in the time/now... and your input for location, temp... in a couple/three months or so your new koi should be a good two, two and a half inches... and starting to show their color/pattern... though these markings will still change/evolve for another year or so. Bob Fenner>

Pond fish crosses Dear folks at WWM--in the spring of 2002 I made an in ground pond that is approx. 1500 gals.  That summer we purchased one Koi and caught four of our neighbor's comets from their pond.  This summer-about two weeks ago I noticed some small fry.  They are dark in color and are growing fast.  Maybe at least twenty of them.  The larger ones are starting to change colors near the heads.  My wife had bought some water hyacinths at a local shop and thought since the plants were kept outside the shop may have introduced some kind of fish to keep mosquitoes down and the eggs may have been in the roots.  On the other hand wondered about genetics if the Koi and comets have mixed?  Thank You <Yes they have! The resulting crosses are most often called "orfes"... Congratulations. Bob Fenner>

Koi and goldfish Dear Bob, <Claire> We have a small pond in our garden and we have 7 Koi, 7 canary yellow goldfish and 3 other goldfish.  Recently we have noticed that they have spawned at some point and we now have at least 30 babies that are living all ranging from about ½ to1 ½.  How can I tell if they are Koi or goldfish and how long will it be before they become a decent size.  They all seem to be living in the foliage in the pond which covers a huge section. Regards Claire <Good question... they might be Koi, goldfish, or actually crosses (orfes)... you should be able to discern the first two pretty soon... Koi are more thin, fusiform (torpedo shaped), and faster swimmers... Rates of growth can be pretty fast during the warmer months... and your new fish/es may grow to be a few inches in the next few months. Congratulations. Bob Fenner> Koi egg?  hi, I have a pond in my back garden and I have 2 Koi carps they have been together a week and there is an egg in the pond where it hasn't hatch yet, I wanted to know if the egg is meant to have bubbles around it, because I cant find anything on the net. the egg is also floating is this ok, or have the adults tried eating it. My email address is xxxxxxxx@xxx.xxx  please reply back  thanks, Rachel  <An egg... as in one? How large is this object? I suspect are seeing something other than a Koi egg... they lay many (hundreds or thousands) that are quite small... like the head of a pin in diameter... maybe you are observing some part of a frog spawn. Bob Fenner>

Koi fry Hello Bob, I have this 150.000 gal. earthen pond, wanted to know if the Koi fry will go to the bottom of the pond after they hatch, and will I be able to see them at the waters edge or on the surface after a while? <Most should spend the bulk of their time near the surface, adjacent the edge. Bob Fenner>

Koi with the hots, because of... the hots Hello Bob, We just had a big surge in temps. here in west virginia-50s during the day to mid 80s. My Koi are going crazy trying to spawn, but I don't think the females are ready yet. For the last two days the males have been chasing but no eggs .Is it the sudden rise in temp. making the males go crazy. Thanks <Yes, very likely... Do keep an eye on the action here... and separate the two sexes if things are getting too "heated" (obvious damage to the participants... males and females in two different areas. Bob Fenner>
Hello ,Wet Web Crew-I'm the guy that has those hot Koi because of the hots. Well they were hotter than we thought, I have fry now. My question is- I have the capability to cool this earthen pond off again by pumping water from a nearby trout stream. In doing so, could I trigger another spawn? Thanks for all of your help this spring. John  <It is possible to do this, but I warrant against it... better to see how many of your current spawn grow out... and be prepared to share them with others. Bob Fenner>

Koi-carp  Hello again, could you please tell me if a grass carp and a Koi can inter-breed, and could I expect any color out of the two? Thank you.  <<Hello, I've truly no idea. Sorry :( -Gwen>>

Koi "breeding on their own" Hello, my name is John Butler, I would like to know the success rate of letting Koi spawn on there own in an earthen pond. I have good water quality. Thanks again, John Butler. <Mmmm, "very good". In all likelihood if you have fish in a large enough (a few hundred gallons plus), of differing sexes... enough food, decent water quality they will indeed breed, many of the young will survive. In actual practice, individuals of both sexes are chosen and the results of their breeding recorded (as this species does not "breed true") for percentage of decent/types young... but they will indeed breed given the opportunity. Bob Fenner>

"Flipping" fish? Hi, Jim here. <Bob here> Saw your website and read/searched for information on my situation but didn't see it addressed. <Okay, let's address it now> I have an outdoor pond, 3 years old, approx. 2500 gallons with a small waterfall. There is a 1250 gph pump, UV sterilizer and gravity filter that runs year round - I'm in North Carolina. I have 3 Shubunkin and 14 Koi. The Shubunkin and most of the Koi were all transplanted into the pond 3 years ago and purchased when about 3" long. Four of the Koi have been hatched in the past two years in the same pond. <All right> In the past few weeks we've noticed that a few of the larger Koi (14-15") have been darting around the pond and rolling onto their sides while swimming. Not for long, only a moment when shooting down the length of the pond, almost like "watch me Dad!". I did notice one of them fanning the bottom of the pond for a couple of days with his tailfin; he hasn't done that since (near as I can determine he's one of the males - long and sleek). I haven't noticed any milt in the water and the females that I can identify still seem full with eggs. <Tis the season> I had written it off to spawning behavior or just plain old Spring fever but last night one of the Shubunkin wasn't feeding. She - Daryl Anne - [Larry, Darrell & Daryl until Daryl laid eggs and became Daryl Anne ;-)] was off by herself and didn't swim with the rest all evening. Very unusual behavior for her as she's always the first to feed and very sociable. <Could be all the goldfish/Shubunkins are females... or that the male is "not mature"> The pond wintered over very well, water is clear and the colors/markings of the fish look bright and blemish free. I added water yesterday as it was down about 10% - treated the city water with Prime as I always do with no adverse effects. Does this behavior sound at all familiar? Thanks! <Does sound familiar. You know that the goldfish and Koi are separate species... but can cross-breed (not usual in your setting)... I do think the Koi were/are just feeling spunky with the warming weather. Do keep your eye on them should they clear the side of the pond and need to be placed back in... Bob Fenner>

Koi breeding...  I've read your story on Koi breeding and I understand what's suppose to happen. I have 2 females and 6 males that I have in a 85 gal. tank inside my home, I bring them inside because my pond outside freezes up in the winter. My problem is they start the breeding stage { the chase } and it goes on tell my females are so tired that they can't move, I never see any eggs or a milky color to the water like anything has happened . I finally take my females out into another tank so they can rest. please what can I do? Please tell me what I'm doing wrong and help my females. thank-you very much   Randy Staton <You will likely need to keep the males and females separated. Bob Fenner>

Goldfish and their Lack of Breeding I have installed an outdoor pond, it holds about a 1000 litres of water. <Sounds like a nice big set up!> I have 23 various Goldfish ranging in size from 2.5 - 7 inches in length. I built the pond in March 2003 (Autumn). It has Water Lilies and other Oxygenating plants in pots as well as a Fountain. The fish all seem extremely happy in their environment, and from time to time seem go through the process of chasing one or the other, which I am told is part of their breeding ritual. <That is a good sign to show the possible start of breeding.> However, it is now February 2004 and we have seen no sign of young fish. This is my first pond and I am really puzzled, can you please help. <The problem is that they might very well be breeding, but the young just aren't surviving.  There are many factors that need to be considered when trying to breed goldfish.  One is that goldfish will lay their eggs on plants in protected areas.  I find the eggs in areas of Java moss, or heavy leafed plant areas.  They don't typically place them on surfaces such as cichlids.  Also, Goldfish don't care for their young.  In fact it's best to separate the young from the adults so they are not eaten. After they eggs are laid, the parents seem to forget and not even care about it.  Other goldfish will nibble the eggs, or if the eggs do hatch the fry are eaten.  Goldfish are not above eating other fish.  One of my largest goldfish (foot long Sarasa comet) had to be removed from it's display tank because it was large enough to eat the other tank mates. Another factor in dealing with goldfish breeding ponds are the predators.  Since the pond is outdoors you can't protect the young fish from the birds, raccoons, and other creatures that will quickly eat small fry that feed at the surface.  My guess is that your fish probably are breeding but the eggs and/or the fry are being eaten before they have a chance to grow.  If you wish to breed your goldfish the best way to do it is to have tanks set up inside your house.  With an area for the parents to lay the eggs.  When you see the fish chasing each other, you can capture them and move them to the breeding tank.  Once they lay the eggs you can move them back to the pond.  Now you can care for the eggs and fish until they are large enough to go to the pond (or you can sell them to the LFS).  This is just a quick overview of what you can do to breed and raise the goldfish if you would like to learn more I suggest you look around in your area for local Koi and goldfish clubs.  There usually is one in most major areas.  Go and chat with people, learn and make new friends.  You will really enjoy yourself. There are many places online that you can find the needed info.  I find that http://www.goldfishinfo.com/ is a great source to start.  Be sure to check back to the WetWebMedia site for new articles and care tips for Goldfish.  We are currently updating and written more in the goldfish area.  Good luck, and have fun with the Goldies! -Magnus> Thank you.       

Control of (Pondfish) Breeding  Mr. Fenner: I read your article on fish spawning and it seems to be directed at the encouragement of reproduction, in a controlled way. We have bought a home recently and it has a lovely pond and we are learning to work with it, but we do not want to have too many fish. All of our animals (cats and dogs) are spayed and neutered and we feel strongly that we should not encourage reproduction of pets, in particular, the gold fish in the pond. I do not want to destroy the excess fish or dump them into ponds where their future is unknown or doubtful. Is there any way to control reproduction with food? I hesitate to suggest any chemical for the water, but any ideas? Donna Schmidt Wichita, Kansas. <Good question (at least for me thought-provoking and a challenge...). As far as I'm aware there is no food or environmental control of goldfish that one might use to prevent their engaging in reproductive behavior... You can try keeping out "floating plant material" that might serve to encourage their activity... but there is no way to sex them when small (so as to keep single sexes only)... or any other manner I'm familiar with... I encourage you to "trade out" offspring or give them to neighbors, children if you end up with excess young. Bob Fenner>

Breeding pond fish hi I am interested in breeding pond fish.  We have a 1500 gallon tank and we have Shubunkins and 3 Koi.  the Shubunkins are laying lots of eggs and they hatch.  Last winter I took about 100 in and put them in an aquarium by themselves and 3 lived.  I had tropical fish for 20 years (not breeding) and cant figure out what I am doing wrong. <Perhaps "nothing". Only a small percentage sometimes develop to this point> I am looking for a good reference book that will last me and give me the detailed info I need. <Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pdfshbreeding.htm and the references at the end>   Also, will the Koi breed with the Shubunkins? <Yes, goldfish and Koi/carp can/do crossbreed at times. Bob Fenner> Eileen  
Breeding Pond Fish
Hi, <Hello! Ryan here today> My Mom has a small garden pond in her yard. We have put regular goldfish in it, (plus one Koi,  which has gotten pretty big), last year and now this year we have noticed  babies, this year more than last, there seems to be different sized ones, from tiny "fry" size to about 2 or 3 inches. <Sounds great!> We have looked every where for info on goldfish breeding but not having much luck, was wondering if you could tell us more about their breeding habits and why our fish are breeding when we are not exactly trying to make them breed, not that it isn't fun watching and discovering the babies. < http://www.wetwebmedia.com/PondSubWebIndex/pdfshbreefaqs.htm http://www.wetwebmedia.com/PondSubWebIndex/pdfshbreeding.htm> Also if there is anything specific we should be doing for them or should we just leave well enough alone and enjoy the show. Mom is wondering if the regular goldfish would mate with the Koi, have no idea on sexes of fish but they are all about 4 to 5 years old. Thanks so much,                                              Nanette and Ilse, Glasford, IL <It sounds as if you are doing a great job- read the links, appreciate what you've created.  Best of luck! Ryan>

Goldfish and mollies in a fountain (06/21/03) Hey how are you ?? I have a quick question for you, <Hi! Ananda here today...> We have a rather large fountain in our courtyard and we put goldfish and black mollies in there, a few of the goldfish are now looking pregnant, will they lay eggs or what is the goldfish reproduction like, and if they lay eggs would the mollies fertilize them <Well, if the goldfish lay eggs, the eggs will be fertilized by other goldfish. Mollies are a very different type of fish; they bear their young live. You might do a web search on "goldfish reproduction" to find out more.> thanks Shannon <You're welcome. --Ananda>

Pond fish dear crew,     A fantail and a comet goldfish in my pond seem to have white pimple like spots on their gills.  I am unsure at what this is, but I have heard this could be related to spawning. Any ideas? <This time of the year (Spring, warming) this is very likely the case. There are some Pondfish ailments (e.g. fish pox) that can look similar, but highly unlikely here> When I was visiting Canada recently I saw a huge goldfish that must have been released there.  We almost caught it with our net. I would have loved that fish for my pond.  Also, next year we are upgrading our pond to about 3000 gallons. What type of liner would you recommend? <The thicker... at least 20 mil, the better... butyl rubber or EPDM, but vinyl will do...> I am currently using EPDM rubber, but if there is a better type I would like to know about it. <Oh! This is fine. Bob Fenner>                                                             thanks                                                                     Holden

Goldfish hatchery Hi my name is John Butler, and I have a question for you. My question is, I'm planning on starting a goldfish hatchery. I need to know if all varieties of goldfish can be raised in earth ponds? Also, what varieties should I keep together or separate? <The more common (Comet, Fantail) varieties are bred and reared in earthen ponds, and more exotic ones can be as well if you have mild weather, consistent water quality/temperature in the area you are using. All should be kept separate by sport/variety. Bob Fenner>                                                                     Sincerely, John Butler

Spawning Nets Hello Bob, I just finished reading your article on breeding Koi and I found it very interesting!  I was hoping you could tell me where I could purchase some spawning nets.  Thank you very much and happy holidays!!!!  Sincerely, Leah  <Please try the etailers, retailers listed on our Pond Links page: http://www.wetwebmedia.com/PondSubWebIndex/pondlinks.htm Bob Fenner>

Re: Experienced Koi Breeder (Career, travel, adventure possibility) Bob, We communicated some times ago seeking your assistance in finding an experienced Koi breeder for our farm in Jamaica. I suspect we may have lost some communications since my mail sever experienced some problems have been unreliable ( hence the msn account) Please let me know if you were able to find someone as we as still searching. Thanks Norman mmfarms@cwjamaica.com <Will re-post your note on our sites. Bob Fenner, WetWebMedia>

Goldfish Hi my name is Gene Mace and I have a question about Feeder Goldfish( I think they are called Comets). <Yes... the "only" variety of this species developed in the United States...> We have a 165 gallon pond that is now 1 year old. We originally stocked it with a couple dozen Comets on the recommendation of an expert who said that when the Comets stopped dying it was safe to introduce more exotic species. We ended up with 7 Comets who have thrived and have grown to about 3.5 to 4 inches. As a result we haven't introduced any other species because I am afraid of over crowding, etc.  <Ah, good for you> Additionally my wife and daughters have become attached to these fish. My question is what are their mating habits? They appear to be doing something but I don't know what they need to be successful. We live in Memphis Tn. Thanks Gene <Please read over the "Pond Fish Reproduction" or such section posted on our website: www.WetWebMedia.com here... Koi are similar in their breeding habits... and you may well have young come a bit of warmer weather, use of live plants... Bob Fenner>

Aquatic Gardens

Ponds, Streams, Waterfalls & Fountains:
Volume 1. Design & Construction
Volume 2. Maintenance, Stocking, Examples

V. 1 Print and eBook on Amazon
V. 2 Print and eBook on Amazon

by Robert (Bob) Fenner
Become a Sponsor Features:
Daily FAQs FW Daily FAQs SW Pix of the Day FW Pix of the Day New On WWM
Helpful Links Hobbyist Forum Calendars Admin Index Cover Images
Featured Sponsors: