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Where, when in doubt... water changes

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

Pregnant pond comet? Using WWM     8/17/13
My comet seems to have been swollen since last summer. She wobbles when she swims. Not sure if she is pregnant or something wrong with her. How can I tell
<... could be full of eggs, egg-bound, a tumour, fatty degeneration due to poor food/feeding... Search WWM w/ your string above and read. Bob Fenner>

Pond... mortalities, reading  06/26/10
I have had a pond now for about 10 years and this year is the first year I have ever had any problems (other than blue heron problems) with it. I can't keep any fish alive. We live next to a lake and each year I fill my pond with lake water and I seem to have really good luck with it.
This year my fish just keep dying. I usually just get feeder goldfish because of the blue herons and I bring them inside for the winter, keeping them for years. The only thing different from previous years is I set a canna lily pot and an elephant ear pot in the water.
<What were these "potted" with?>
I have since removed them but the fish are still dropping off. Last year I made a bog with a pitcher plant and it did very well and didn't seem to affect the pond any. I'm now wondering if maybe this is a problem also.
<Not the plant/s, but the soil perhaps>
The fish seem to get a whitish coating near the back fin before they die.
I would like to know if I'm doing something wrong or have I just been getting bad fish.
<Highly likely something is amiss with the system, not the livestock>
I only get the cheap feeder fish
<These almost always have a plethora of health/parasite issues>
as it gets to expensive buying better fish to feed the herons.
<You should read on WWM re guarding against such predators:
and the linked FAQs file above>
The water in my pond also seems to be staying very clear which is unusual. Every year it gets some green algae but not this year. The weather is very unusual this year and I have been putting the clear water down to the weather. I really enjoy watching the fish in my pond and will be very disappointed if I can't keep any alive to watch.
Any suggestions on what I might be doing wrong?
<Yes... read here: http://wetwebmedia.com/PondSubWebIndex/pdenvdisfaqs.htm
and all the linked files above. Bob Fenner>
Re: Pond... mortalities, reading 6/26/10

> Hi Bob,
> I did see the pond question earlier today, but left if you to answer since the problem wasn't obvious to me.
<Nor I>
> However, one thing that did catch my eye was the bit about pitcher plants. Growing carnivorous plants is a hobby of mine, and one thing true about them is they're bad choices for ponds. They invariably need acidic, mineral-free water to grow; lime causes damage to their roots, and eventually death. So if the pitcher plants are thriving in the same water basin as the pond, then alarm bells should be ringing -- anything soft and acidic enough for Sarracenia spp. North American pitchers would be lethal to Eurasian pond fish. Conversely, if the pond was alkaline enough for the fish, any pitcher plants used as marginals would be dead by now.
<Will accrue your input>
> So at the very least, employment of a pH test kit would be very useful.
> Cheers, Neale
<Thank you, B>

Police report filed after several fish die at local Koi competition -- 01/13/2010
Geez, I hope this wasn't foul play. BobF
Re: Police report filed after several fish die at local Koi competition 01/17/10

Yes, most likely foul play. Contestants of past contests have complained about fins and tails of their prized Koi sipped off. The pressure to win is intense.
<Yeeikes! And ridiculous. BobF>

White warts over Koi  12/18/08 Greetings, <Salutations> I enclose a picture of a chagoi that has not been great all year. I was finding odd feces floating in the pond- white mucoid, very large and jelly like, sometimes slimy. I had numerous scrapes of fish taken, microscopic examination of feces done- nothing discovered. <Mmm; too small for light microscopy...> As winter approached, the fish developed white spots, large and cyst like all over the body (not the fins). The fish has acted strangely at times by holding its head out of the water in the inlet (this is a 20 inch fish). No other fish appear to have these symptoms or spots. The fish has not flashed, sulked or looked otherwise irritated. The water is currently at 4-5 degrees, holding very steady. I have many contacts here in the UK, none of which can explain these growths. The white spots are very raised- resembling zits, and are around 2mm big. The water quality is, and always has been immaculate. Testing regularly. I have kept Koi for many years- this is new to me. Many thanks for any help.. (I have kept the photo at full size, so that you can zoom in and see the detail of the spots) Julian. <I do wonder that this might be a case of Spring Viremia... Do please insert this term in your search tool... much written re its pathology, due to occurrence amongst economically important food cyprinid species. Bob Fenner>

one-sided bloat... Pond goldfish... need data   7/8/08 Clear Day Hello, <Overcast here howdy> I am writing about a pond goldfish. I searched the site first and read about fish bladder problems, but in this case the goldfish is bloated on one side, <Not from the gas bladder... perhaps a tumour, maybe ovarian activity...> does not have signs of dropsy, has no overt injuries, missing scales, ulcers, etc. It is able to swim but lists to the 'flat' side. Appetite is good. I first thought it was carrying eggs, but does not seem to be the case. <There goes one part of my guess> This happened last summer to another goldfish, that survived for many months in this condition before succumbing. The PH, nitrates, nitrites etc, are within normal range. <Values please> It is a very healthy pond, and the other fish are unaffected. Thank you for your quick response, as I would like to help this fish survive. Laurie Kross <Need to know the make-up of the pond, water quality tests, maintenance procedures, foods/feeding... Please read here: http://wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm the section on Pondfish Disease. Bob Fenner>

Koi are dying left and right - please help! Hello - <Hi!  Sabrina with you today> I have had my 500 gallon pond for 2 years and have never had a problem.  All of a sudden, last week my Koi have been dying one by one.  I found another 3 dead this morning -- two 12" butterfly and a 10" regular domestic Koi.  This makes 5 dead Koi since last week.   <How many fish are there/were there altogether?> I have examined the fish and have found nothing wrong.  For a few days they appear lethargic, anti-social, and do not eat --- then the third day they die.  I have not introduced any new Koi in to my pond lately.  I do regular water changes -- about 20% once a month.   <Depending on your fish load, this may not be enough (or it may be just right).  Have you tested your water lately?  Check your pH, ammonia and nitrite right away, see if any of those values are outta whack, it sounds like this might be water-related> They only thing I could think of is all the rain we have been getting in NE Ohio recently.   <Possible.  That might affect pH, and too huge a pH change might cause the fish harm - but that's a real stab in the dark.  Has anything else changed?  Feeding regime/type of food, water conditioner, anything?> I'm lost.  I'm sad.  I'm frustrated. I'm confused.  Did I say sad?    <I'm sorry :( > My local pet shops don't have a clue.  Please give me any help you can.  One more thing -- my Shubunkins, Sarasas, and goldfish are doing fine -- why is this?   <IME, Koi are a little more sensitive than goldfish.  Whatever's affecting the Koi probably is affecting the goldfish too, but to a lesser degree.  Check your water parameters, and fix if necessary.  Best of luck to you!> Thanks - <You're welcome> John

Koi are dying left and right - please help!  (Part 2) Hello again - <Hello again, John!> Thanks for the fast response.  I just went out to my pond to check on my fish and I lost two more Koi.   <Sorry to hear that.... :( > However, all the other Koi that have died showed no physical signs of illness.  But the one of the two Koi that just died had a white fungus on it.  It was quite severe.  Why would this fish have a fungus and the others show no signs of fungus?   <Could be that there's something else at play as well, that's not as easily seen, and this fish, weakened but still alive, ended up contracting the fungus where the others just hadn't yet?> And why would this fish die after the others if it's in worse physical condition? <He may have just been a stronger fish overall, and the fungus finally did him in> To answer your questions . . . I had five 10-12" Koi three 4" Koi four 4" Shubunkins maybe 20 goldfish (all small) and two Sarasa (about 4") <This really seems a bit much to me, for a 500g pond.  Illnesses can spread like wildfire in high stocking densities, and fish waste can build up rather quickly, worsening environmental conditions> (again, all my fish that are not Koi are still alive.  I down to two Koi) I've now lost 6 Koi within 24 hours. <I suggest you catch a few, one at a time, and take a close look at them in a clear container.  Look for the fungus that you saw, and anything else amiss; look especially for white stringy feces, as perhaps you're dealing with something internal, which may explain why the fish have looked more or less undamaged externally.  Check the color of their gills, their rate of breathing.  It might be a good idea to try treating with MelaFix, as it does have antibiotic properties; I'm really not convinced as to its effectiveness, but I've used it in conjunction with other things and gotten results.  might be worth a shot, if we can't figure out what's ailing them (aside from the fungus).> Ammonia and Ph levels are testing out fine.  However, my  water hardness is on the high side. <I assume you mean ammonia is zero?  I don't think I'd be terribly concerned about the hardness, unless it's WAY off from the norm, or has been changing dramatically.  Do check your nitrites/nitrates, though, and see where they're sitting.  Also, the next time you get a chance, you might think about collecting/testing the rainwater and see what that is as compared to the water in the pond and from your tap, or whatever source you use for water changes.  Another long shot, how often do you check your filtration system?  Perhaps that's gotten out of whack somehow, or gotten really gunky?  Have you used any gardening chemicals/weed killers/anything else like that that may have gotten into the pond with all the rain you've been getting?  Any next-door neighbors uphill from the pond that might have done so?>
Re: Koi are dying left and right - please help!
Thanks again for your prompt help.  I had no deaths so far today (but then again I don't have many fish left).  We did look at the gills of some of the dead Koi last night and they looked nice and pink.  No parasites.  Also, to answer your question, the nitrates are checking out fine.  I also pulled out some of the fish as you requested with a net and examined them and found no noticeable defects or parasites. My filtration system is clean as I'm religious about my weekly cleanings.  No gardening or insect chemicals have been sprayed around or near the pond that I know of.   I have purchased some MelaFix and added it this morning.  Is there any other recommendations for medications that you may have?  Also, if I'm unlucky enough to have another death and end up dissecting it what should I be looking for?  Thanks again. <Reading over this correspondence brings back bad memories of years past when we had service accounts that suffered similar sudden "anomalous" losses of pond fish. I want to add an emphasis on having some of the dead fish checked for pesticide residue... a spray truck (usually for wood termites... in the ground or structures) can account for this sort of wipe out... and be a few blocks away. Bob Fenner>

Koi are dying left and right - please help! (continued) A pond shop in Akron might know what the problem is.  As you suggested, it's more than likely a parasitic problem.  I didn't  mention in my previous e-mails that my pond is located in the shade surrounded by several trees and a bird feeder.  The pond shop thinks that parasites may have entered the pond via bird droppings.   <Yes, this is possible, especially if you have birds coming that visit local ponds, streams, rivers, etc. - glad the store could help you, and I hope you've located the problem at last!> I have since relocated by bird bath and feeders to the opposite side of the yard.   <Great.    This may help prevent recurrences of the same problem (if, in fact, the birds did bring something with them), but do understand that it's impossible to eliminate the threat altogether; birds come to ponds, and the most we can do is be vigilant and keep an eye open for anything wrong, as you have been doing.  Although I've no direct experience with birds bringing in parasites (thank goodness!!), I have heard of similar cases.> I have purchased parasitic treatment and I hope my pond is on it's way to recovery.   <Excellent  - but please do not discount the possibility of pest control poisons.  Keep your eyes open, and see how the fish respond to the treatment.  With all due luck, you've found the problem.> I have two more sick Koi that appear lethargic.  I hope they make it.   <Our fingers are crossed!> Thanks for all your help -- seriously.  I can't  believe that there are people out there that care for the Koi of strangers.  It's nice to know that people like you exist out there. Thanks! <And thank you for the kind words!  -Sabrina> John Trafan

Mysterious Death Hello, <Hi.> Im thoroughly confused. <Me too, a great deal of the time.  This condition can often be easily combated with books and other resources concerning the topic(s) which confuse you.  Oh.  Wait.  There's more to this, isn't there?  Something fishy, perhaps?> I have just found a dead goldfish floating in my pond.   <Sorry to hear that.> The pond is about 12ftx20ftx3ft deep (at its deepest point) and has been established for about 5 years (2 comets, 4 goldfish, 5 Rudd <I had to look "Rudd" up; I've never heard this common name, nor seen pictures of this Eurasian cyprinid.  Cool looking fish.> and numerous sticklebacks). <Sounds good, so far.> The fish is about 4 years old and is approx 6 inches long and appears in perfect health all the fins are intact and the colour is fine <Sounds excellent, minus the bit about being dead.> I thought it was just resting but it was on a slightly strange angle (maybe dead for an hour or so at most I think) and the fish is a good weight and size and has no outward signs of disease or parasites or damage etc. The temperature is probably btwn 2-6 degrees Celsius and there has been no ice on the pond for a few weeks now (I'm in the UK) It is the first fish I have lost from the pond (apart from the odd stickleback every few months at worst) <First thing to check is water parameters - find out where you're sitting for pH, ammonia, nitrite, and nitrate.  It would also be a good idea to check your oxygen level.  Another point to consider, are you feeding the fish? At these cold temperatures, the fish cannot benefit from the food, and it really only contributes to waste buildup, which can cause ammonia, nitrite, and nitrate to rise to perhaps toxic levels.> I am a relatively experienced fishkeeper (6 years tropical/coldwater) and I just dont get it?  Do you have any idea what could have caused this? <In all honesty, this may be a completely unsolvable mystery.  It is entirely possible that the animal died of something unexpected and sudden, just as other animals and people sometimes do.  Dissection may shed some light on what did him in, but other than that....  Test your parameters, rectify if necessary, and don't lose too much sleep over it, at least.  Everything sounds good otherwise, really.> Many thanks,  Paul Newman <Any relation to.... no.  No, I am *not* going to ask that.  I get enough "teenage witch" comments, I can understand where you'd go nuts if I asked you that, so I'll refrain.  Wishing you and your pond well,  -Sabrina, neither teenage, nor a witch>

It's Not Easy, Bein' Green....  06/20/2004 Hi, <Hello.> I have a large outdoor pond (1400 gal).  Two of my goldfish developed a green fungus on the skin on both sides of their bodies. <Wow, now *that's* something wholly unfamiliar to me.> One died, the other just developed the same symptom.  Do you have any idea what it is?   <'Fraid not....  I'll be hitting the books, though, and see if I can find anything.  Meanwhile, if you could please respond with ammonia, nitrite, nitrate, and pH readings, that may be of help.  Also, any other symptoms the fish may exhibit - lethargy, clamping of fins, any marks or discoloration (besides the green), perhaps also describe the green fungus in a bit more detail (fluffy, stringy, grainy, bright green, dark green....)> How to cure it? <Sorry I'm not of the greatest help, at the moment.  Please do respond, though, and know that I'm trying to find any info on the situation as you describe.> Thanks for the help. <Hoping to be of better service,  -Sabrina> <<Likely env. at base... RMF>>

Koi with sudden Curvature Of The Spine? Hello, thank you for running this awesome site.  One of my Koi, 11 months old, about 7 inches long (approx 1 inch less than others his age) and while they appear to be maybe overweight, is in good shape but not as heavy.  He/she is an orange and white Kohaku and I have often thought in the last month or more that it had developed a slight kink where the body meets the tail itself. <Not good... thank you for the useful info. above... such twisting/kinking is likely genetic here... though can be infectious (e.g. Myxosoma), nutritional in origin> All Koi are growing like crazy, eating out of my hand, surfacing to allow me to pet their heads, except this one? Now today I noticed that it is bending its back third of its body most of the time making it swim crooked and unbalanced.  In fact with its body straight while motionless, it lists to one side and stops the listing by suddenly kinking the last third of its body (approx. from the rectum back?) It seems quite bad?  So my questions are:  If it was normal at birth, why is it now developing a Curvature of the Spine or whatever is happening?  I switched to a higher protein food in the last month or two.  They are fed some Wardley's Pellets and Wardley's Tubifex Worms, some Nutrafin Spirulina Algae Flake Food and some Hikari Gold Pellets.  Averaging out the protein comes to 40%. <Mmm... I would offer "regular" Koi food prep. (pelleted) foods... better nutrition and MUCH less expensive.> Water temperature is consistent at 68.5 degrees Fahrenheit.  I vacuum off 20% of the water daily, removing all traces of debris on bottom of tank. <This much protein is "okay" at this temperature, but it would be better for your Koi to eat less protein percentage... like twenty percent maximum, and grow more slowly... will live longer, healthier lives...> My well water straight from the well has a pH of 7.0  High range pH of 7.4  Nitrate 10 and Ammonia between 0 and -.25 as so hard to decide on the color graph with my Master Test Kit on that Ammonia?  Well water is tested safe for Human Consumption every year. <Then it is fine, I assure you> Tank is consistent at pH 7.6  High Range pH at approx 8  Nitrite is always 0  Nitrate around 80+  And that Ammonia comes in around -.25??? Just don't know, MAYBE it is 0 but the color test strip makes me suspect from yellow (0) and kind of a yellow/lime colored (.25)??? <A good idea to store, aerate new water ahead of use... like in a covered plastic trash can, for a week> Bio filter is cleaned every 14 days.  Foams, pads and carbon is cleaned, bio stars and rings are not flushed with tank water more than every 2nd or third cleaning? <Ah, you've been studying!> Tank is a 200 gallon galvanized aluminum stock tank. <Mmm, hope it's "old"... the galvanization, aluminum can be toxic> Also Aquarium salt is kept at  less than 1/2 recommended amount for freshwater aquariums.  4 growing Koi and 2 tiny Comet Goldfish. Water is added back each day after vacuuming as close to 68.5 degrees as possible, rarely out more than .5 degrees. Any chance you can explain to me what is happening with this Kohaku?  I am thinking it might just be Genetic but certainly don't want it to start happening with my other 3 babies who are more excellent quality.  Thank you kindly, Gayle <Ahh, we concur re the cause here. I would just enjoy this specimen... it may survive for years... Not a contagion at play here. Bob Fenner>

Help!! Koi problem! Hi, <Hello> We are having a problem with our Koi and I can't find a similar problem/answer anywhere. Hope you have and idea. <Let's see> (first a bit of background) My daughter was lucky (?) enough to win a "goldfish" at her school carnival about a year and a half ago. <Like giving away "the first pack of Pall Malls..." this is how many of us "got started" in this wonderful interest/hobby> (Figured he/she was a feeder fish a wasn't really thinking he'd last too long) Started him/her out in in small tank ( 2 Gal). Fishy got bigger. We moved him to a bit larger tank (5 Gal). Fishy got bigger. Ok... notice a pattern? We have since moved Fishy to a 10 Gal. tank and he's still getting bigger (about 9-10 inches). So, we have made plans to excavate in the backyard and install a pond. (as you may a have surmised, Fishy the goldfish is actually fishy the Koi! ) <I see... unusual... usually are comet goldfish that are given away> The problem is this, Fishy has always had a nasty habit of snacking on the gravel in the tank. To curb this, we changed to a larger sized gravel (more like stones). This took care of the problem for a bit. Now, as Fishy has grown, so has the size of his mouth. The bigger rocks are no problem now. Usually, in the past, he has managed to either "pass" or regurgitate the gravel/rocks.  Currently, he doesn't seem to be able to do either AND his tummy area is looking quite large. He doesn't seem interested in food....very odd for him and seems to hover (head down/tail up) in the tank much of the time. Is there anything that can be done? I've taken all the gravel/rocks put of the tank but, I'm worried that this time he's eaten way more than he can take care of on his own. <I strongly suspect your fish is either "just fat" or "full of eggs", but in case it has swallowed rocks, I would add the equivalent (you may want to move the fish into smaller quarters) of a level teaspoon of Epsom Salt per ten gallons of water...> Any help you can provide would be appreciated. Kathy <The Epsom is safe, and should help dislodge whatever the cause is here... Please do read here: http://www.wetwebmedia.com/PondSubWebIndex/pdfishfeeding.htm re pond foods, feeding... in case the cause is actually nutritional. Bob Fenner>

Egg-bound pond goldfish Hi: We have a white goldfish that we've had for more than 10 years - in a small outdoor pond. She is very large (with eggs, we think), but has been this way for more than one week. There are only three other fish in this pond - two are from her and the other was purchased with her (also 10 years.) Anything we can do to assist her to release the eggs. She is moving very slowly and we are worried about her. <You might try adding Epsom Salt to the system water... the equivalent of a level teaspoon per about ten gallons of system water> In the past, the other white fish would "chase" her, but, this does not seem to be happening this year. S. Robison <Bob Fenner>

Pond injuries, disease We have a 700 gallon backyard pond with waterfalls, plants and 15 fish. The pond is well established, about 6 yrs old and we've added salt and test the water etc. Seems fine. I have 2 questions. 1) Fish periodically get sucked into the skimmer basket... <Do fashion a screen over the front of this> ...and are usually fine when taken out and put back in the pond. We have one fish that was hiding for about 2 days and I finally found it and it seems to be swimming like a rolling barrel and then resting on the bottom. Should we euthanize this fish? <I would wait, see if it "straightens out"> 2) Another fish is acting normal and swimming around with the others but I see what looks like a couple of algae (green) threads drifting up off of 2 tiny spots on the back near the top fin. I can't find anything about this. Is this something to worry about? It's a new one on me. The rest of the fish look fine and healthy. <Net the fish out and examine this area carefully... this may be a crustacean disease... remove with tweezers, and daub with Mercurochrome, Merthiolate or

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
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