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FAQs on the Molly Health/Disease 8

Related Articles: Mollies, & Poeciliids: Guppies, Platies, Swordtails, Mollies by Neale Monks, Livebearing Fishes by Bob Fenner,

FAQs on Molly Disease: Molly Disease 1, Molly Disease 2, Molly Disease 3, Molly Disease 4, Molly Disease 5, Molly Health 6, Molly Health 7, Molly Health 9, Molly Health 10, Molly Health 11,
FAQs on Molly Disease by Category: Nutritional (e.g. HLLE), Social, Infectious (Virus, Bacterial, Fungal), Parasitic (Ich, Velvet...), Genetic, Treatments
FAQs on Molly Reproduction/Breeding
Molly Reproduction 1, Molly Reproduction 2, Molly Reproduction 3,

Mollies, hlth.  - 4/17/12
Danielle here again.
<Hello Danielle,>
I have 5 adult balloon mollies- an orange female and she's the one I've had the most and my favorite, 2 creamsicle females, a female with a silver top and white bottom, and a creamsicle male. 8 days ago I brought home the two newest ones. 1 creamsicle male and 1 creamsicle female. I bought them at a place I shouldn't have for the first time, I regret it very much, and that will be the last time. I got them at Petco. I don't have a quarantine tank unfortunately- and never needed one before I went here because the place I always go is so great. The place I usually go to is called That Fish Place That Pet Place. They take unbelievably great care of their fish. All of their staff are either biologists, seasoned hobbyists, or some other sort of trained professional.
<Real good.>
Most of the time they quarantine them themselves. Every time I've seen them restock they always have tags reading under observation for such and such amount of time. I have NEVER had a problem and now my whole tank is infected with something. The one that has it the worst is one of the two I just brought home.
There are two spots on his gills, well the outside of them. They're white and I can't tell if they're his scales that are irritated or cottony looking stuff.
They are in the same spot one on each side and only in that one place that he rubs. There's nothing on the rest of the body. Unfortunately I can't get a picture of him or any of them, they're too squirmy. Plus they're flashing off the bubbler tubing, filter, and rounded decorations. I read on here that salt and higher temperature will work if I don't want to use medicine.
I started that yesterday. but I also noticed that that post was from 2003.
So I hope that's still true/helpful.
They always had brackish water with marine salt in(instant ocean to be specific) - .5oz/1 gal. So I upped it to 1oz/1gal. and the temp is up to 84.
<This should help a good deal. Do also treat with an antifungal, and ideally one that knocks off Finrot too -- e.g., Seachem Paraguard.>
But I'm still really nervous. The other fish don't have the white spots on their gills but they're all rubbing/flashing off their gills like the male.
Except for 2.
The one is the fish I've had the longest and another is a younger one. But I figured if everyone else has it they're just not showing signs yet.
I thought since I had the salt in, that I wouldn't have much to worry about and I didn't until now. I do 30-50% water changes about 2 times a week. I tested the PH today and it was at a 7.6 like usual. I haven't gotten a nitrite/nitrate test yet but I have it ordered.
<Ah, would check this. In brackish water, Mollies are normally bullet-proof, but Balloon Mollies are obviously very inbred, and the result is less hardiness compared to the "real McCoy".>
I do use water conditioner though. Every time I fill, replenish, or clean.
I even add it if I noticed babies were dropped or anything dead. With the frequent water changes I would think there shouldn't be that much of a problem.
<I agree. And normally, Mollies are fine in mature brackish aquaria.>
For over 3 moths I've had it set up and until now its been perfect. Its really frustrating when you spend so much time taking care of it, watching it grow, and money and then have it all go down the drain. I also have a tank for when they have babies. But that tank is fine since I didn't put any of the sick ones in with them. I did try tetra life guard for two days but that just seemed to make it worse and was a waste of money.
<Would tend to agree. Many of these inexpensive, cure-all medications aren't that reliable. Okay as preventatives perhaps, when you have a fish that's got damaged but otherwise seems just fine. But not something I'd reach for when fish are visibly sick.>
Plus I don't even know what the issue is so I was hoping you could tell me.
They don't clamp their fins, swim around lively, eat A LOT and their colors are still beautiful. I hate to see them suffer. There are a few babies in with them and I was going to move them to the baby tank but I didn't want to infect the others- there's 135- 3 different ages and they won't stop popping them out!!!!
<A lot of fish!>
I never had a male until 8 days ago but the tank at the store wasn't lacking in the males. I know they can store sperm for a while but gosh how many batches can they have!?
<Many; some relatives of the Molly have produced six batches from one mating. Do bear in mind juvenile males as young as 2 months can be fertile.>
My favorite has had 3 and looks like she will have more, my black one has had 2, and one of the creamsicles( the one from That Fish Place) has had 1 but there were only 7 from her. I've noticed after each batch the number grows as they grow/get older. The biggest batch I've had so far is 70 and that was from my black one. But of course I have lost a few from natural dyeing off and getting sucked into the filter but not many suffer that fate at max 5- I have saved a few from it. 
The black one is in the baby tank. She's rude, mean, temperamental, and tortures the other adults but leaves the babies alone.
<Do bear in mind Mollies are very hierarchical and far from peaceful, and a healthy big Black Molly will often bully weaker examples of delicate strains like Balloon Mollies.>
I don't know what her deal is but she's quite happy in the baby tank.
<Fair enough.>
She's been that way since I brought her home so it's nothing new. Im trying to find them homes and our LFS is willing to take some when they get big enough.
I don't know if it makes a difference but there no gravel or substrate in the tanks, I don't like it and I feel like stuff just gets stuck in it. I do have decorations and plenty of hiding spots.
Sending you pictures that I should have had with my other email. One should be of the tank, one should be of a creamsicle fish the one I got at Petco, and the other should be of the male fish with a circle around where the spot is. This is the tank as of right this moment. The creamsicle actually didn't have that color at all when I got her from Petco. She barely had any color at all and now she's a beautiful gold. I don't know if its because she was unhealthy at the store, naturally turned, the food I'm giving them(all of the fish's color have gotten more vivid and beautiful since I bought them) or what but she looks great. Then there's the male with the spot on his cheek. It's exactly the same on the other side too but I couldn't get the other side.
<I'd use a good, reliable antifungal, anti-Finrot medication together with the salt/heat you're already using. Seawater dips for 20 minutes at a time would be useful for the specimens with obvious damage/tufts. Seawater is 35 grammes salt mix/litre, and you only need to make up a litre at a time, so it's a cheap way to blitz the pathogen. Mollies should take 20 minutes without problems, but if it keels over before then, return it to the brackish water. Cheers, Neale.>

Re: Mollies   - 4/18/12
Will API fungus cure work? that's the only thing I can find around here that seems to get good reviews. What you mentioned they don't have around here.
<Should deal with Fungus. Has no effect against Finrot. So wouldn't be my first choice. Do hunt online if possible for a good, reliable medication that treats both Finrot and Fungus at the same time (though not a tea-tree oil type product like Melafix that *says* it treats both but usually does neither). Waiting a day or two delivery shouldn't kill the fish, especially
if you do the seawater dips daily. Cheers, Neale.> 

Re: Mollies    4/18/12
Thanks so much for all your help. You guys are really awesome and your website is great.
<Kind of you to say so. Cheers, Neale.>
Re: Mollies    4/18/12
One more question. Can I put the old filter cartridge back in or is it a better idea just to use a new one?
<Carbon and zeolite ("ammonia remover") need to be replaced regularly anyway, every 2-3 weeks. But biological media (sponges, ceramic noodles) should be rinsed (ideally in aquarium water) and reused as often as practical. If you must replace biological filter media, replace no more than 50% within a 6-week period. Cheers, Neale.>

Re: Mollies    4/20/12
So I've noticed slight discoloration on the creamsicle Balloon Mollies on the top of their heads. It looks like dry skin and then its slightly dark under. It doesn't look too intense. Will it clear up as soon as I clean the tank and treatment is over? I saw in the post: "Re Balloon Molly with "cracked dry spot" and discoloration on top of her head. Please HELP!
that it could be from medicating. It looks just like that except not nearly as bad. I'm just hoping its nothing to worry about once treatment is done.
They're all still lively and eating well(little pigs actually). I have been doing the 20 minute salt dips like you suggested. They seem a lot livelier after I do the dips.
<Mollies like seawater!>
The flashing seems to have calmed down a lot. I have Seachem's Paraguard ordered just incase this does not clear up with API fungus cure. I really don't like this whole medicating thing. No filtering, no water changes, its cloudy but I don't want to ruin the purpose of the medication.
<Don't understand this. Any hospital tank needs a filter, either biological or else zeolite (ammonia remover) replaced on a regular basis.
Alternatively, treat in the main aquarium. If the fish are dumped in an aquarium without a filter, they'll be stressed by the ammonia, and no amount of medication will help them.>
I do have oxygen circulating and the filter is on just no carbon cartridge.
Is there anything I can do to keep it clean yet not ruin the whole purpose of medication? I read on Seachem's website about the Paraguard and it says that you don't need to take out your filtration. Is that true? Nitrate and Nitrite test should be here today - I tracked the package and it says out for delivery. And just to make sure I have it right - everything should be at 0? Except the PH of course.
<Ammonia and nitrite need to be zero. In brackish water, nitrate level isn't crucial, but certainly below 40 mg/l, and ideally below 20 mg/l.>
Thanks so much,
<The discolouration seen on Mollies is quite common, as it is with Black Moor Goldfish, and I suspect for the same sorts of reasons, excess mucous production, perhaps couples with patches of dead skin and/or skin parasites (e.g., Slime Disease/Costia). Generally clears up fine if treated for whatever ails them. Cheers, Neale.>
Re: Mollies
It says to take out the carbon filter. What do I do to keep the ammonia down? or should I just ignore taking out the filter
<Carbon has nothing to do with ammonia. So yes, you always remove carbon when medicating (except if you use salt or Epsom salt, in which case carbon doesn't have an impact either way). Ammonia is removed through biological filtration (i.e., sponges and ceramic noodles in use four 6+ weeks to become mature) or zeolite ("ammonia remover", which needs to be replaced every few days, as per the manufacturer's instructions or when you start detecting non-zero ammonia levels). Few medicines effect biological filter bacteria, but some do; refer to the manufacturer's instructions on this.
Cheers, Neale.>
Re: Mollies

Here's what the directions exactly say: For best results remove activated carbon or filter cartridge from filter and continue aeration.
<Yes: they are talking about carbon. Not biological filtration. You leave biological filtration _in situ_.>
For each 10 gal of water empty one packet directly into aquarium. Repeat does after 48 hours. Wait another 48 hours and then change 25% of the aquarium water and add fresh activated carbon or replace filter cartridge. Note this medication will discolor water and may stain aquarium sealant and ornaments. Use API BIO CHEM ZORB or activated carbon 48 hours after final treatment to remove color from water.
<Pointless unless the medicine is toxic to specific livestock, such as shrimps, but feel free to spend your money this way if you want…>
This package treats up to 100 gal. Two doses required for full course of treatment.
I was really confused by this because I know ammonia and all that other stuff is terrible. So what do I do?
Thanks, Danielle
<Cheers, Neale.>
Re: Mollies    4/20/12

Got my kit and my Nitrates if we count for fw: 10 or sw:20 and nitrites are 0
<Sounds fine. Time for less chatting Danielle and more reading! Do see the WWM articles re:, and then apply that knowledge yourself. Cheers, Neale.>

Mollies... worms? Lernaea... ?   3/20/12
Hi there WetWeb crew.  I have a tank with Mollies of various breeds and ages.  I noticed that a couple of my fish had Ick so I turned up the temp to 82F, took out the activated carbon, and did an ick treatment and repeated 48 hours after.  Now I see the ick is gone but it is replaced by these dark brown/red worms that are attached to the fish's tail.  I did another ick treatment thinking it might work. What are these worms?  Is my tank done for?  What can I do?  Hope you can help, Jacquie.
<Are the worms attached to the tail fin, or are they emerging from the anus, just in front of the anal fin? If the latter, these are likely Camallanus. If just keeping Mollies, switching to strongly brackish conditions should break the life cycle of either worm type; perhaps one-quarter salinity initially, SG 1.006, about 9 grammes marine salt mix per litre of water. Cheers, Neale.> 
More re Mollies, worms   3/20/12

Another possibility: Lernaea. Read here re:
Bob Fenner
More re Mollies, worms   3/20/12

Another possibility: Lernaea. Read here re:
Bob Fenner
<Ah, do agree Bob, hence recommendation for strongly brackish water, which should shift (almost) all kinds of external parasites… standard operating practise on fish farms, with salt-tolerant Salmonidae, Cichlidae. Even better, Jacquie, if Mollies can be moved to half-strength or full-strength seawater for an extended period… hours, days. Perhaps doable with buckets? This is one of the real advantages of brackish water fish… the relative ease with which external parasites can be controlled, eliminated. Cheers, Neale.>
<<I do agree. Thought I'd add the poss. for review's sake. BobF>>
Re... FW worm poss.    3/21/12
Wow!! Thank you Bob and Neale  I was not expecting such a response from you and in such a timely manner.  I can assume that if one fish has these worms the rest of them probably have them too, I just can't see them yet.  The worms themselves are only on the fins there are no sores or red spots or marks of any kind and there are none coming from the anus.
<Do send along a well resolved pic please>
 The ick is completely gone and I will put the carbon in tomorrow.   Now all I have is mollies (got rid of the golden algae eater as per your advise)  so can I just make their tank heavily brackish rather than using a bucket?
<You could, yes>
  I have a twenty gallon tank so how much salt, in tablespoons, should I put in to make the salinity high enough.
<... please learn to/use the search tool/indices....
  The tank itself is already semi-brackish I will just deduct how much I have already put in to what you say.  And how long do I leave it like that?
 Also what caused the worms to begin with?  I have not bought any new fish in well over a month.  Was it the ick?  Thanks again Jacquie.
Re Mollie Worms    3/21/12

Hi, Jacquie here again.  I just want to make sure I have this conversion right.  You said 9 grams per liter.  I have a 20 gallon tank/ 75 liter. <So, 9 grammes x 75 litres = 675 grammes. Sounds a lot, I know, but seawater contains 35 grammes per litre, so if this was a marine aquarium, that'd be about 2.6 kg, well over 5 lb for a 20 gallon aquarium! If you don't believe me, check out the salt at your local retailer: a 3 lb bag makes about 10 US gallons. By all means use the measurements on the marine aquarium salt package you have. If it says it makes X gallons of water for a marine aquarium, you want about 20-25% of that amount for X gallons of brackish water. Does that make sense?>
So I am putting 675 grams of marine salt in my tank which is about 2 1/2 cups of salt.
<Yes, but NOT ALL AT ONCE! Make up a brine solution, adding the required 675 g salt to, say, a couple litres of hot water. Stir it in thoroughly; dechlorinate. Remove a couple litres of water from the aquarium. Then, over the next couple of days, add portions of this, maybe 10% every 2-4 hours, half one day, and half the next. That'd give time for the aquarium filter to adapt. The fish couldn't care less, but the filter bacteria might.>
It sounds like a lot but if you say its right I will do it!  I want to rid this tank of the worms.  Thank you in advance.
<Most welcome. Cheers, Neale.>

Sick Male Balloon Molly 2/11/12
Hi there! I have a Balloon Molly that I purchased about 4 weeks ago. He was very healthy up until now.
<Ah, I see where this going. Let's start by making the point that Fancy Mollies are not easy fish to keep even at the best of times, and Balloon Mollies, being extremely inbred and very deformed, are even more sensitive.>
Just recently he stopped eating. He looks fine he still swims normal but slower and spends more time at the top by the heater or down on the bottom in a corner. What is wrong with him? He is in a 20 gallon, brackish,
<How much salt what sort? If your water is already very hard, then aquarium salt is fine. But if you have soft water, you really do need to use marine aquarium salt mix because that contains minerals that harden the water.>
81F, tank with 9 other molly tank mates that are all perfectly healthy.
<Is a lot of Mollies for 20 gallons; as I've mentioned many times before here at WWM, Mollies need space. Anything less than 30 gallons isn't reliable, and because male Mollies are so aggressive (and females often pretty feisty!) bullying is common.>
It is filtered with 2 aqua clear 30s. (3 insert filter system- foam, carbon, bio rocks)
<Do remember carbon removes medication.>
I put some more aquarium salts in this afternoon hoping that would help some what. I feed them flake food, cucumber, peas and blood worms. Is it dropsy?
<My assumption would be bullying. Although Balloon Mollies have the same aggression levels as other Mollies, but can barely swim, they pick fights they can't win, and end up bashed about a bit. They're best kept among their own kind and not regular Mollies. In a big tank with lots of floating plants or their plastic equivalent Mollies can sort of get along. But in a small tank, and 20 gallons is small for Mollies, social behaviour becomes a problem.>
He does not seem overly swollen, his tummy may be a little distended but he is a Balloon molly after all. (Lol) He has no spots or fungus. I also have not seen him poop in a while. Any advice would be greatly appreciated. Thanks Jacquie.
<Cheers, Neale.>

Black Molly, floating... 2/7/12
I have a 32 gallon fresh water tank, I use a Fluval 304 filter. I keep it very clean.. I have 5 molly fish (different kinds), a angel fish, two loaches, and a sucker fish. They eat TetraMin tropical flakes. I use salt in the tank also. I have kept up the tank for two years. I never had any problems Until today, my black Molly was floating around uncontrollably with the current from the filter and the bubbles. I noticed his top fin was missing, paying more attention after awhile I noticed one of the other Mollies bothering him so I removed him, and placed him on a smaller tank. He ate when I put food in his tank, afterwards I noticed white transparent stuff hanging off him, So I put Quick Cure for ick and Lymphocystis in his tank. Now he has something that looks like small bubbles all over him. Is there anything I can do for him?
Can he survive in with the other fish without his top fin? Will it grow back?
<Hmm'¦ do read here:
Mollies need much different conditions to Angels and Loaches, so your problems here are very likely environmental. Do review the needs of this species, and act accordingly. Do also understands that randomly adding medications will only make a sick fish sicker. Imagine your doctor didn't bother checking you out and instead gave you the first bottle of pills he came across! Cheers, Neale.>

help, Molly ill Re: A Newby~ Question about fish compatibility for stocking a tank, and population control 2/4/12
Hi again, Neale,
I'm having my first real issue with the Mollies! I worry that it's because I waited....I wanted to make sure I had everything stable and surviving first before adding a new type of fish, and I was planning on finding Indian Glass Fish somewhere-- (Lala's because they're smaller) before switching the Mollies to brackish because I thought, if they did carry the Glass Fish in freshwater, it would be so much easier to switch everyone to brackish at the same time... So I added 2 tbsp regular aquarium salt per 5 gallons for now to carry over... doesn't look like it's enough, or could my filter be absorbing the salt?
Now a Molly died, and a second one looks like it's on the way out. The only symptoms are, lying at the bottom of the tank and breathing heavy. 29 gallon is normal- that's also why I expect it's Bacterial Gill Disease.
It's 0 Ammonia, 0 Nitrite, 0 Nitrate, 7.2 PH, Alkalinity is 80, Hardness is 75, and Chlorine & Chloramine are 0.
I've listed the treatments recommended below, as I don't know which treatment to use due to having fry in the tank and a filter issue, so please advise!
[redacted text from another web site]
The trouble is, I currently have a filter that has the carbon inside of it, so I can't really remove the carbon without removing the entire filter to do the medicine!
<Then that's what you have to do. As I've stated many times on WWM, buying a filter with non-removable carbon is a bad idea. Low-end filters often go this way because saying they include carbon makes them sound attractive to less experienced hobbyists. In fact carbon is almost totally useless in the average freshwater tank.>
Should I buy some sort of sponge and put it in the slot in place of the filter when I do the treatment?
<So long as you don't lose the mature biological media, yes.>
Problem with that of course, is the sponge won't have bacteria on it.
<Then you have a problem.>
Though, there IS a plastic catcher that is put in with the filter that does have bacteria colonized on it. So, is it ok to take out the filter entirely?
And do I need to put something in it's place?
<You must have some way to remove ammonia. This is one of those situations where using zeolite (ammonia remover) may be worthwhile, but unfortunately it isn't very effective once you add salt to the water, so you'd need to keep the salt level low (1-2 g/l) and overestimate the amount of zeolite.>
Will the treatment kill the fry????
I was kind of hoping one would grow up and have the coloring of the other poor fellow I lost.
The other possible cause could be stress from a bully, though the way she's breathing I think it's illness... and I haven't observed the orange fish acting bad lately, however, one of the guys mentioned that right before they give birth they turn very aggressive.... which now explains what happened with the other three females that I moved into the 10 gallon when they acted up. Now that tank is swarming with little orange fry and the fish are skinnier!!! The orange fish IS pudgy, and she's been aggressive in the past, but I really think the fish at the bottom is ill. If it dies, do I still treat the whole tank to make sure no one else comes down with it?
<Worthwhile, yes.>
There is also a weird issue with the 10 gallon!!! And I'm worried about the little fry in that tank. Please advise.
10 gallon is 0 Ammonia, 0 Nitrite, 0 Nitrate, 6.8 PH, 120 Alkalinity, and Hardness is 75, and Chlorine & Chloramine are 0.
The fish store had me buy something to up the PH since I have Mollies and they tend to be fussy. My concern is, no one is sick in that tank, and there are all of those babies!!!! Will it hurt or stress out the fry if I add the PH up product? Or should I wait?
<You shouldn't change the pH directly; that's risky. The fish shop half-understands what's going on. Here's the science: Mollies get sick in soft water. Soft water is water with a low mineral content. Water with a low mineral content tends to have a low pH. Hence Mollies tend to do badly in acidic water. But there's a chain there. It's a case of correlation rather than causation. The Mollies get sick because of the low hardness.
The low pH is caused by the low hardness. Sick Mollies and low pH are both caused by low hardness. In itself, the low pH (probably) isn't the major factor that kills Mollies. If you have soft water, your job is to harden it. If you harden the water, the pH will go up anyway. If all you're keeping is Mollies, or at least alongside salt-tolerant fish such as Guppies and Glassfish, then using marine aquarium salt mix is the easiest way to fix things. Marine aquarium salt mix isn't just salt but also minerals that harden water. Add around 5-6 grammes per litre of water, and the water will suit your Mollies perfectly! Alternatively, if you want a plain vanilla freshwater system, use the Rift Valley salt mix. It costs very little and is easy to make.
Depending on how soft your water is, 25-50% of the described dosage will be required for a mixed species tank. Mollies and other livebearers would be even happier with the full dosage.>
And do I need to feed the fry anything special?
There's algae on plants and rocks and they nibble it, and I think some flake food sinks to the bottom too... I thought maybe there would be enough food for them to forage since they do like algae... but since I'm asking the other questions might as well clarify that too.
<Molly fry need plenty of food or they won't grow properly, so don't underfeed. As with any baby fish, aim for 4-6 small meals a day.>
Also, in the 10 gallon I have the granite chips. I wonder if this caused the drop in PH as they are super neutral and add nothing. I'm thinking about adding the Texas limestone rock that I removed from the 29 gallon when the PH climbed...to maybe help it climb a little. I don't want it too steep though. Do you think that would be a good idea?
<Adding limestone to a Molly aquarium is a very good idea. It will (slightly) buffer the water. But it isn't a fix for low hardness.>
Thank you. I appreciate all of your advice. I suppose I should start going to brackish asap after I treat the 29 gallon.... I shouldn't have waited.
<Cheers, Neale.>
Update: help, Molly ill 2/4/12

Well, the pet store's open till nine.... I decided I need to take action tonight and bought Tetracycline. The guy said that the babies will probably survive, no guarantee, and gave me some filter medium to use...
I still don't know about the PH. He said don't touch it if they look happy.. Do you agree?
<See previous message.>
I used inside water on the 29 --- the softener had run out of potassium.
<Hang on'¦ are you using water from a domestic water softener in aquaria? No wonder you're having a hard time. This is NOT a good idea. Domestic water softeners do not soften the water, regardless of the name. That's why they're so cheap (per gallon water) compared to reverse-osmosis filters that really do remove all the minerals and soften the water. Domestic water softeners ONLY remove what plumbers call "temporary hardness" and aquarists call carbonate hardness, measured in degrees KH. This is the stuff that buffers pH and keeps it stable. Remove it, and all you have is the general hardness (degrees dH) left behind. This "permanent hardness" doesn't cause lime scale, which is why plumbers don't care about it. In the aquarium it's useful enough in its way for how fish manage osmoregulation (the water balance in their bodies) but it doesn't buffer pH at all.>
I had the Texas limestone in there that I ended up removing. Ph was 8.
<pH 8 is ideal for Mollies.>
Then I did two water changes in time, each time using outside water which had a slightly lower Ph. I started the 10 gallon with water from the change and outside water.
I still don't know why it went to 6.8! Outside water tested at 7.5.
<Without carbonate hardness, which is removed by your domestic water softener, pH will plummet in the aquarium between water changes. Do read:
Are the little kits better than the strips as far as accuracy?
<Generally, yes, but shouldn't make a huge difference.>
If my water starts averaging 6.8 .... That would be totally frustrating, as they say we're so hard here! That's why I chose Mollies over say Cherry Barbs and Tetras and a Sparkling Gourami. I wanted to choose something that would be happy with the water I have, same reason why I don't plant Azaleas! Oh well. I guess if it's more difficult than I expected, I'll gain experience.
<Hard water, if left alone, can be an excellent medium for fishkeeping so long as you choose the right species.
Cheers, Neale.>
Re: help, Molly ill 2/5/12
Thank you, Neale. It sounds like I just need to go brackish ... I'll return the PH booster.
The aquarium was purchased as a kit. None of the items separately could have been purchased so inexpensively together (it even had included the heater), and the filter is super quiet. That it has the little rubber bacterial trap in the filter is at least helpful so it won't have to re-cycle each time it's changed- I'm not removing the bacteria each time.
One of the top local fish shops is reported to use ONLY sponge filters.
Maybe a sponge along with the filter medium inside of the box could work temporarily.
<Sponge filters are excellent. But they work by being a place for bacteria to live. In and of themselves they don't remove ammonia.>
I'll go to that fish store today. Since they're entire store is sponge, they can probably advise me how to convert it at least temporarily.
Though they have sponge filters even on their brackish. I need to read your article on it before I go to see what I need for the brackish system.... If sponge would work and were the least expensive, it might have to do for now until I can invest in something more modern.
<An air-powered sponge filter is an economical and effective filter.>
Thanks again.
<Cheers, Neale.>
Re: help, Molly ill 2/5/12
Thanks Neale.
If my poor babies survive, then after I finish treating the 29 gallon (five more days!) I'll move the other 3 adult Mollies back there. Then I can move the two fry in the 29 to the 10 gallon in with the tiny orange school of fry. This way I can give all of the fry better circumstances with no adult competition. For some reason the orange fry like the java moss but haven't paid any attention to the huge mass of hornwort I added for them! So giving them private quarters is best. If I raise them right, maybe I can trade most of them for a whole bunch more brackish tolerant plants, as it sounds like this will be helpful if I have a sponge filter, along with more frequent water changes and whatever else I'll need to do.
<Indeed. Do read:
Lots of salt-tolerant low-end brackish plants that thrive with Mollies.
Many cheap as chips.>
<Cheers, Neale.>
Re: help, Molly ill 2/5/12

<Welcome. Neale.>
Re: help, Molly ill
Good news, the baby fish finally discovered the hornwort. They are so cute....!
<Good to hear, Jill. Now, before Bob gets annoyed about chit-chat <<Too late!>> on the
Daily FAQs, let me remind you that discussions about aquarium successes, fishkeeping ideas and whatnot are best enjoyed over at the WWM Forum, here:
See you there! Cheers, Neale.>

Help! My balloon Molly seems really sick* 2/4/12
Hi, I really appreciate your willingness to help, and I'm sorry to come back with the same question, but I've read for hours... I've Google searched, and looked at just about the FAQ, there was a lot of really great information, but I couldn't find a case like mine, that offered help. maybe I missed it?
<Hmm'¦ from the photo, you seem to have the standard issue environmentally-stressed Molly. Lack of hardness, low pH, insufficient warmth, introduction to a new aquarium without a mature filter; that sort of thing. Common symptoms include patches of white mucous on the body and face, clamped fins, rocking from side to side, the "Shimmies", lethargy, and eventually a mysterious death. There's usually not much point to medicating, if the conditions aren't fixed, and you haven't yet told me anything about the water quality or chemistry.>
I've learned that there is A LOT to know about taking care of mollies and I still need to educate myself. In the meantime, I don't live in the USA, and all pet stores will be closed here until Sunday, so my only chance is home remedy until then.
Any ideas how I can help her? She seems to be getting worse, fins are moving more rapidly, although she has eaten. None of the other fish seem sick (yet'¦) But I see she's distressed, and I'd hate for her to die if there's any way to help her. I don't have bacteria in my tank, but as per instructions from the store (yesterday) I had put salt in.
<What do you mean by "no bacteria" in the tank? Is the aquarium new? It needs to have its filter cycled for a good six weeks to become mature. Mollies simply don't do well in new tanks, so I wouldn't keep them in an aquarium that was less than 3 months old.>
I replaced a third of the water again today, but it doesn't seem that's helped. Should I add more salt?
<How much are you adding? A good amount for Mollies is 5-6 grammes of marine aquarium salt mix per litre of water. That's about SG 1.003 at 25 C/77 F.>
Should I give her some greens? (is broccoli or spinach good too?) heat or cool the water?
<The water should be between 25-28 C/77-82 F.>
I'm afraid to move her out of the tank because I don't have anything else with a heater. I've attached a picture of her, just resting on the filter, don't know if it helps.
Any suggestions how to help her until then?
Thank you! from me and my mollies :-)
<Hope this helps. Cheers, Neale.>
Help! My balloon Molly seems really sick 2/3/12

Hi I've searched ur forum and can't find anything like this. My 3 month old balloon Molly started leaning back and swimming head up. At the store they told me to change a third of the water and add salt. I thought for a moment it helped but she continued doing that and started resting at the bottom of the tank. Today - 3 days later - she's hiding near the heater and won't eat. She also stopped using her tail completely and is mainly head up. the store told me that she probably has a propeller birth defect that only showed up now and that there is nothing to do. But honestly it doesn't seem they care too much so I was wondering if they could b wrong? Is there any chance I can save her? The info of my tank; its a small one with a sponge filter cuz I got them as newbies. There r 5 guppies and 1 other balloon Molly all the same age plus two baby mollies. The temp is 26 degrees cel. And my water snail died for no apparent reason the day b4 but my store now thinks it's a coincidence.
<Hello! Please do start reading here:
What aren't you doing that you should be doing with Mollies?
Do then peruse the following page and the Molly Disease articles 2, 3, 4, and 5 linked at the top. Chances are, you're dealing with some sort of environmental issue that others have faced before. Lack of hardness, low pH, high nitrates, an aquarium that's too small; all these are common.
Brackish water conditions, though not essential, do help.
Cheers, Neale.>
Re: Help! My balloon Molly seems really sick 2/3/12

Thanks so much for the speedy reply.
<You are welcome.>
I will research the links right away.
But do u think it could actually b this birth defect that erupted suddenly?
<No; genetic defects will be apparent from birth. Cheers, Neale.>

Suddenly Dead Mollies 1/26/12
Dear WWM Crew, <Hiya Julie!>
We started a new heated and filtered 10 gallon tank 12 days ago for my 8-year old son.
<Excellent! I was introduced to fish what I was about that age. Too bad I couldn't keep any alive! I do think I do a bit better now.>
It has gravel in the bottom, one set of live plants and a few plastic plants, along with a ceramic/plastic decoration that looks like some coral and shells with a tunnel through it. Water temperature is 76-78 degrees. A day after we got the tank started, we introduced 2 Dalmatian Mollies (1 male, 1 female) and 1 female Black Molly.
<Oops! A couple of mistakes here. Firstly, you need to give this tank time to cycle. Are you familiar with the nitrogen cycle?
do read here -
Secondly, mollies are not the ideal starter fish. They need quite exacting conditions and a larger tank. Here is a bit more on the subject - http://www.wetwebmedia.com/fwsubwebindex/mollies.htm
One of females had babies two days later. We saw five babies originally, then after a day there were 4. At some point in those first few days, we moved a Blue Mystery snail from a Betta-only tank to the new tank. We were somewhat worried that the snail was getting fed, because the Mollies seemed to like the snail's TopFin Algae Thins.
<Aha yes, trying to get some greens into their diet. Not uncommon. In fact, quite necessary as part of their regular feeding.>
After 5 days, we added 3 red Glofish, and the pet store recommended Omega One Veggie Rounds for the snail. For a number of days, all fish seemed fine, swimming and eating normally, and in the case of the Mollies, I would say voraciously, even on the snail food--now the Veggie Rounds.
<And as a result of this feeding, adding to the toxins that would naturally occur in a new, uncycled tank>
On day 10, we found the Black Molly dead on the bottom of the tank. The snail didn't look good either. On day 11, the snail still hadn't moved, but we weren't absolutely sure he was dead. On day 11, we got a new black Molly.
<Okay, so here's the deal. This tank is suffering due to the reasons mentioned above. I would suggest you take a step back, read the above links and act accordingly.>

When we introduced her to the tank, one of the babies was gone and another didn't look too healthy--not swimming much, staying right at the top of the tank. All other Mollies seemed OK last night--swimming around as usual, though not so hungry on the second feeding. This morning, day 12, all three adult Mollies were dead and only one baby was alive and the snail was definitely dead as well. The only problem that we know of is that at times my son was overfeeding (TetraMin plus tropical flakes), but the tank water didn't look bad.
<Not about how it looks. Needs to be tested for toxins such as ammonia which I am sure you will find. A good test kit will become your best friend as you find your way through this hobby.>
I've never kept fish before, but my husband has (as a kid), and he too is puzzled about what could cause fish that seemed normal the night before to be dead by morning.
<One word - toxins. When you read the first link I have posted above, you will see what I mean. The short answer is that this tank was neither ready nor right for the fish. With a little bit of reading, I am sure you can introduce your kid to a fascinating and sustainable way to keep these amazing creatures alive and well. I notice you mentioned you have a Betta.
I hope you have provided the right conditions for it. You can find more on keeping this fish by using the search tool on WWM>
Also, what do you recommend to help the remaining fish stay alive? 50% water change?
<Won't solve the problem permanently but will help reduce toxins for a bit.>
Anything else?
<Oh yes! But it is all said above>
<Good luck Julie! I do hope you find the information you seek and that you kid is able to enjoy this amazing hobby!
Cheers, Sugam>

Disappearing Mollies 1/19/12
I am quite stumped. I have a 75 gallon highly planted tank that I am responsible for here at my school. In this tank are the existing fish: 3 Tiger barbs,
<Need to be in bigger groups than three; six or more.>

2 Skirt Tetras,
<These too; and like the Tiger Barbs, can become nippy, aggressive if not kept in adequate numbers.>
2 Rosey barbs,
<Subtropical fish.>
1 Glowlight tetra,
<Schooling fish.>
1 tinfoil barb,
<Will grow HUGE!>
2 female platies, 1 small Pleco (about 5"),

<Not small for long. Assuming this is Pterygoplichthys sp., will reach 45 cm/18 inches. The Bristlenose Plec, Ancistrus, gets to about 12 cm/5 inches and is a more sensible selection.>
and variety of snails. When I started there was a request to add Angel Fish and black Mollies.
<Which need completely different environmental conditions; can't be kept reliably in the same tank.>
So 5 Black Veiled Angelfish (most recent) were added as well as 2 Black Lyretail Mollies and 5 Black Mollies.
<Oh dear.>

Well, initially two black Mollies were lost, found remains and all and the Mollies were fine when I left mid December for the break. My boss was taking care of the fish while I was gone (even my fish, who are all just fine). When I got back with the Angelfish (cause I picked them up from a breeder at home), there were only 3 Black Mollies and the two Lyretails. I asked if he had seen any fish die, he said no and now, on the 16th, I noticed that another Molly was missing. Yesterday, one of the Lyre-tails went missing, but I found one black Molly later that day unable to swim and with a bent spine. I am highly confused as to what is causing this.
<I'm not.>
I've sat and watched the tank, the Tiger Barbs spend more time chasing each other through the plants, they don't even chase the Angelfish. They are too large to get sucked into the filter intake. The tank stats are a follows: pH 7.5, Ammonia 0, Nitrite 0, GH 180, KH 80, Nitrates 80.
<Nitrates LETHALLY high for Mollies in freshwater; 20 mg/l is the MAX for Mollies in freshwater.>

The water here abnormally hard here, but for some reason it refused to go lower in that tank.
<What? This water is fairly hard, yes, but if your tetras and barbs are happy, then it can't be "abnormally hard" because they're soft water fish. Conversely, Mollies need VERY hard water if you're brave enough to keep them in freshwater rather than brackish water. I do hope you aren't trying to change the pH of the tank directly.>
It's not even that high in my two tanks. There is no salt in the water,
<One of potential problems.>

and I have three month old Molly fry here that are doing flawlessly without it.
<Molly fry for some reason aren't always helpful. For a start, 20-50 are born in a clutch, so just because one survives simply proves that large numbers of them died for one reason or another. Whether predation or water chemistry or water quality is hard to say. But just because you have a single fry don't assume that means you're doing something right. It doesn't.>
As for the Nitrates, before I started they were well over 200 as no one ever cleaned this tank, so they have improved,
<But have far to go'¦>
but the KH was too low for me to even remove small amounts of water without upsetting the tank, so now that that is better...I can finally work on cleaning gravel.
Do you have any ideas what is happening to these Mollies?
<Yes. Nitrate; wrong tankmates; perhaps wrong water chemistry.>

There are no physical signs of stress in this tank.
Thank you,
The confused student.
<Do read:
Cheers, Neale.>

Molly Fin Trouble... 1/20/12
Brittanie here.
I have a silver lyretail molly, new addition to my freshwater tank. He is a greedy guts and a happy fish but he seems to have either come with (got him 2 weeks ago) or grown "fuzzy" not overly so but they don't have a definite outline, "spheres" on the top corner edge of his side fins that are white, they are lumps. I haven't seen them grow in the last 3 days but on one side they seem heavy enough that he's not opening the fin fully. So far he hasn't lost any fin and is swimming and eating well. He is in a 15 gal freshwater tank. My tank parameters are NO3-2ppm0, NO2-0ppm, hardness 300ppm, 0 chlorine, 120ppm alkalinity, and a Ph of 7.2-7.8, ammonium 0 and tank temperature of 70 degrees Fahrenheit. Hoping you can help. Oh, also he is currently eating tetra brand flakes with gusto. Can you recommend an algae food that would be better for him?
<Tetra itself makes a few algal foods, including flakes and wafers; but there are several other companies that offer these as well>
I've tried the sinking wafers
<Try pressing these against the glass... usually they stick and are more obvious and palatable to fishes that don't live much of the time on or near the bottom>
with no results for my Oto though he seems to like boiled zucchini (have read through some articles that have been posted and am now going to try some other veggies). My tank currently contains 2 phantom tetra, a black skirt,
<Can be feisty; esp. when not in a group/school>
the previously mentioned Oto catfish, and a 3ish year old red tail shark
<And this... a tremendous bully at times>
all inhabitants are doing fine and have been for a long while except the molly. Hoping you can help, any advice on my molly would be appreciated!
Brittanie :)
P.S. attached is the best pictures I could get of him...He wasn't very cooperative.
<I can imagine! This pectoral fin looks physically damaged to me... Do keep your eyes open for signs of bullying... the shark or black skirt of what you list in particular, though the Oto may be trouble as well. No treatment is advised. Bob Fenner>

Re: Molly Fin Trouble... 1/20/12
Thanks for the food advice! Didn't realize the wafers could stick to the glass XD them sitting on the bottom is probably why they weren't being eaten. Huh. Since I lost one of my black skirts to a case of one-eye PopEye they have gotten along splendidly. I've heard that about the sharks, so I picked the healthiest looking, least bullying one I could find and she seems to do fine with only minor chases of fish out of her "cave." Never injured anyone but I do watch her like a hawk! The Oto?? I had no idea!
Alright, thanks a BUNCH for the advice your website is of tremendous help!!!!
<Ah, welcome. BobF>

Poop problems, molly   2/27/12
I have a 29 gallon tank. All of the water parameters are fine.
<... need values, not commentary>
I have 1 black molly, 1 Cory cat, 1 platy, and 1 retail shark.
<The last can become very mean>
 This is a fairly new tank which has finished cycling. The only 2 original fish left are the corycat and the molly. The other 2 were added about 2 weeks ago. I had another corycat and another molly before adding the shark and platy but they both died during cycling.
<Shouldn't have been there ahead of the process completing>

 I have a marine land BioWheel filter for a 50 gallon tank. The water temp is 75-80 degrees.  All of the fish are eating fine and generally seem healthy. However, my black molly has been pooping very thick white feces for a few days now. One of the original fish did this at first but died soon after. At that time it was thinner and stringy but with my molly it's extremely thick and sometimes an inch long!  The gravel at the bottom of the tank is covered in it. We did a very large water change and vacuumed the gravel 2 days ago but the gravel is covered in it again!  The molly seems fine and is eating. I feed them flakes every other day and sinking pellets every other day for my shark and Cory but both the other fish way those too. All of the fish get along..no fighting etc. I have read that stringy white poop is sign of parasite but as I said this is very thick...almost pasty like. Please help!  Will attach photo.
<Mmm, as this fish is still about, swimming... I suspect there is nothing dire going on w/ it... Colour, size and frequency of defecation is due to several factors... what's fed, the psychological state of the animal, environmental conditions... This one might just be picking at the white substrate in your tank. I wouldn't panic, nor treat this fish... but would read on WWM re the water quality, nutritional needs of all you list. Bob Fenner>


Balloon Molly with "cracked dry spot" and discoloration on top of her head. Please HELP!, env., no data or rdg. 2/20/12
Hello WWM Crew, thanks in advance for taking my question! I have a Balloon Molly (named Odette) who does not look well. I bought her about 3 weeks ago and very soon after I got her I noticed this problem develop and grow. She has a spot on the top of her head that is whitish/grayish, with tiny bits of orange too. It looks kind of like a humans dry cracking skin, with grey discoloration underneath.
(Im attaching a pic) This spot has more than doubled in size since I got her, but otherwise she acts just fine.
No problems eating, she swims quite happily, etc. Ive also tested her water and that seems fine too. I currently have her in a 1 gallon filtered aquarium with 8 of her babies that are 1 week old.
<Change the water daily>
I had planned on getting a 20 gallon tank for them, but I am trying to fix this problem before I continue with that plan. The molly had been in a 5 gallon
<Much too small...>

with a sunset platy, but the platy began to chase her constantly, nipping at her fins,
so I removed her and put her in the smaller aquarium with her fry 1 week ago. This move doesn’t seem to have affected her
in any way; however the “spot†is still growing and has now spread down her nose and up to the fin on her back.
About 2 weeks ago I purchased Kordon's Rid-Ich
<... see WWM re this product>

Plus Disease Treatment for protozoan or fungal external diseases and followed the instructions but it doesn't seem to be doing anything. Last week I got aquarium salt and added that, but this hasn’t made a difference either. I don’t want to over treat her by blindly trying everything in the store, but I’m worried about her and want to do something! The clerks at the store haven't been helpful, so I'm hoping yall might know what to do. Thanks again! Alisha
<... No data of use. Read here: http://www.wetwebmedia.com/FWSubWebIndex/mollies.htm
and the linked files above. Bob Fenner>

Re Balloon Molly with "cracked dry spot" and discoloration on top of her head. Please HELP! 2/20/12
Thank you Bob for your quick reply. I am doing 40% water changes every other day, so I will increase that. I also read your links about mollies, but I don't see anything that addresses this growing discoloration on my molly.
<Not directly, not likely. The area is discolored from the ill-effects of crowding/metabolite poisoning, and the use of the medication product>
I am really hoping that you can tell something from the picture I attached and the description of flaking looking scales with dark spreading discoloration underneath. I tried the Kordon's Rid Ich Plus as a hope, but my molly's illness doesn't look like the pictures I've seen of Ich, no salt like bumps, nor is it furry or cotton-y like other pictures of illnesses I've seen, and it's isolated just to the top of her head for a few weeks now. I am checking the water levels regularly and they seem ok. If I'm not giving you data of use, can you tell me what I should be giving as useful data?
<See examples from where I referred you... Water quality test results, maintenance, history of the systems, foods/feeding... Search and READ before writing.>
I am a new fish owner and am trying to do the right thing by this fish.
I've read a lot about them before the purchase and after, but I don't see anything that addresses this. I am coming to you as a last effort, I don't know what else to do. I guess I am hoping for a direction to go: fungal, bacterial, internal, diet, etc?
<Environmental as prev. stated>
I am feeding her regular fish flakes,
<... see/READ on WWM re Molly nutrition>
but I was thinking of getting some medicated flakes, do you think this would help?
<No, it won't>
Additionally, will any medication I add to the aquarium hurt the eight, 1 week old fry that are also in there? Will medicated flakes be ok for the fry? They don't currently seem unhealthy in any way. Thanks again for your help, Alisha
<This fish doesn't have a biological disease... BobF>

Re Balloon Molly with "cracked dry spot" and discoloration on top of her head.  Please HELP!   2/28/12
thank you again for your quick response! I apologize if i didn't follow your guidelines for asking questions, I will try to do better.  However I am still concerned about my Balloon Molly and have one last question.  She is still white/flakey discolored, and increasingly so,  with dark underneath discoloration that has spread down her back to her tail, and she is now hovering at the bottom of the aquarium, however she is still eating well . 
I and currently doing a  50% water change every day, and am feeding her a variety of flakes, algae wafers, and frozen blood worms in small quantities 3 times a day.  Her 8 fry, which are with her, appear to be happy and healthy.  They are currently in a 1 gallon filtered tank, which i know is entirely too small, however the 5 gallon they were in with a sunset platy was poor, because of the severe aggression of the platy.  I have been preparing a new 25 gallon tank for them,
<Thank goodness>

 and the water tests look good however it has only been 4 days cycling (I have added the filter from the old small tank, as well as some water, and a decoration),
<See WWM re spurring the cycling process on:
and the linked files above>
so I am hesitant to put them in just yet.  Currently their 1 gallon water tests prove: nitrate=0, nitrite=0, hardness=25, chlorine=0, alkalinity=180, ph=7.5.  I have quit any medications, per your advice that the problem was environmental, and my question is this: is there anything I can do for her in her current tank until the 25 gallon is further along, or should I put her the larger one and hope for the best?
<Read the above...>
 the 25 gallons water test prove :nitrate=0, nitrite=0, hardness=150, chlorine=0, alkalinity, 180, ph=7.5 (I adjusted the hardness, but the rest is the same as the 1 gallon)thank you again for any advice you can offer!-Alisha
<Hang in there! BobF>

pop eye 2/15/12
Hi, I have three balloon molly females. It's a 20 gal tank. One is orange, one is black, and the other is white and orange. I have a bubbler in the back (i don't know if that is ok for them or not).
<Of some value>
I read somewhere that having excess gasses in the tank can hurt them but I don't see where that would be true.
<Not these sort, size bubbles, no>
The heater is set to 78 degrees. I use water conditioner every time I add water into my tank and I change it often. However I do keep them in totally fresh water
<Of what quality? Should be hard, alkaline... Have you at least read on WWM re?>

but I know you highly recommend having salt in it for the mollies. I recently noticed that the orange and white one is being picked on. She's smaller than the other two. Now, today, I noticed she has pop eye in one of them. I don't know if its from them picking on her, bumping into something, a fungus or infection. Its a little cloudy around the top of her eye. The most aggressive one now, the orange one, will go out her way to swim across the tank and nip at the others especially the little one. and if they come near her corner she's at them too. The other one did that for the first day she was in there so I put her in the net and she stopped. I the orange one in a net for now Im hoping she'll calm herself and knock it off.
I also noticed they are slightly fat and getting bigger. I know the one had a batch of 9 babies last week but Im not sure who had them. They have black spots but the orange one looks skinnier. I removed them from the tank accidentally squished one(which I felt terrible about) and the others are still alive and doing well in their own tank! :) I know they can store sperm for a while. I was wondering if they get grouchy and territorial when they're pregnant.
The one that's getting fatter is black and every morning I notice she's on the bottom right corner, I tap the glass to get her attention, I feed them and then the rest of the day she's up and about like normal and hangs out by the heater or the filter sometimes. So I was wondering what to do.
I've really been considering putting salt in but when I got them from our local pet store they were in the completely fresh water section so I don't know if it would be a shock to them to add it in just like that. I don't know the conditions of the water because I don't have any kind of tester, they're a bit expensive here(broke college student...ha). I'm trying to give them the best care I can.
Thanks! Danielle
<... Read here: http://www.wetwebmedia.com/FWSubWebIndex/fwpopeyefaqs.htm
and the linked files above each. Bob Fenner>

Molly Breeding 1/9/12
So about two maybe three weeks ago I purchased some fish:
5 neon tetras (one of which has died, other is missing?)
1 pearl Danio
1 leopard Danio
2 blue Danios
2 Dalmatian mollies
1 black lyretail molly
3 (cant remember the name they're white) mollies

In all, 15 fish. I have a 20 gal. tank and they all seem to have enough space.
<That is WAY too many fish and not the right types for this tank. Please use the search tool to read up about the species you are stocking and their unique requirements.>
I don't do water checks, though I did add some aquarium salt, for my pearl Danio had itch. Which is much better now. The water temperature is set at 72 degrees.
<Too low>

Should that be warmer? <Yes> Well, about 2 weeks ago I noticed a small baby fish hiding out near a plant in the bottom of my tank. I was surprised as I had only had my fish for a small amount of time! <Yup! One of more of the mollies must have been on the verge of releasing fry when you got her.>
Also, fish give birth to more than just one at a time, so I am currently questioning what happened to the rest of my babies! I thought more than just one would survive.
<Likely eaten by the other fish in the tank. Fry need to be sheltered until large enough to be with adult fish.>
Since then, I separated the baby and put him/her in a floating breeder tank, he looked scared with no place to hide so I put a plant in with him.
When can I put him in with the other fish?
<Just as soon as he is large enough not to be eaten.>
Recently, my black lyretail molly has been sniffing? the other fishes' undersides and then they dart away. I'm almost certain that the lyretail is a male and also the Dalmatians. But the lyretail has also been doing the same thing to the males as to the female white mollies. What is he doing?
Is he just being aggressive? Thanks!
<Male mollies are always on the look-out for a breeding partner. Likely yhr behavior you are observing. Simple way to tell if it is male for sure is to check the anal fin. Again, you can use the WWM search tool for details.>

mollie doesn't seem to be adjusting like the others 12/27/11
I'm new to fish ownership lol. We have a 10 gallon tank and have 2 mollies, 5 very small tetras,
<... stop. Mollies need very different water... hard, alkaline, often cooler... than "small tetras". I.e., they're not compatible>

3 small guppies and a plecostomus.
<And this last... unless a species that stays very small (there are a few, but not nearly as popular as ones that get larger than this tank), it will not live long or well here>
I have a few questions. A. Is that too many fish for a 10 gallon tank?
B. Is adding a tablespoon of salt ok for the other fish?
<Likely not enough to suit the mollies and not be toxic to the tetras>

C. All the fish seem to be adjusting fine except one mollie who seems to just stay at the bottom darting back and forth. 2 of the guppies seem to be swimming around it quite close. The mollies are twice the size of any of the other fish. Are they picking on him/her? If so, what do I do about it?
<Please read here: http://www.wetwebmedia.com/FWSubWebIndex/mollies.htm
and use the search tool on WWM to find out the needs of the other fishes you have jammed in here. Bob Fenner>

I think my balloon molly is overdue 12/19/11
I have a, used to be bright orange molly, but within the past month and a half she has nearly tripled in her belly and is white and within the past 2 days i noticed her scales on her belly are no longer touching they look like they're overly stretched out. I've looked for that black spot I've read about figuring it would be easily spotted since she's white right now. But i don't see it I also can see the vent opening like she could have the babies at any time but that has been at least a week now. I have a boy in there and at first he used to peck at her and now he just goes and does his own thing.
<Do read here:
Without any further information my assumption here is that pregnancy is nothing to do with her swelling (though she may well be pregnant as well).
Sounds more like she has Dropsy, a problem largely caused by poor care. To recap, Mollies need a large aquarium (30 gallons/100 litres minimum); hard, alkaline water; excellent water quality (0 ammonia and nitrite, and nitrate below 20 mg/l); and ideally slightly brackish conditions. Mollies aren't beginners fish, and when beginners try to keep them in small freshwater tanks, they usually end up sick or dead. Dropsy, Columnaris, Finrot, Fungus and the Shimmies are all especially common problems with Mollies. Most aquarium books do state that Mollies do best in brackish water, but sometimes people buy them without reading, and that's when the problems start. So, read the above article, find out what it is you aren't doing, and act accordingly. Cheers, Neale.>

Help! I think my Balloon Mollies is dying! 12/9/11
<We state/ask that people limit their graphics files to a few hundred Kbytes... yours are 8 megs... deleted to make room for other's mail>
First I want to say that I think your site has the best information, whether it is brutally honest or not!
Second, I am writing about my Mollies.
I have two in the same tank (10 gal.)
<Too small for Mollies... see WWM re their systems
with a breed of small catfish (not sure what its name was).
<And these are likely intolerant of the salt the Mollies need>

My 10 gallon tank is new and I let it cycle for about a week.
<... not long enough to cycle. Do you have Ammonia, Nitrite present?>

I introduced one Molly first (male named macaroni&cheese) then added another molly (female named molly that gave birth about a week later to 30 fry) and the catfish (tom) about a week later.
At first the two mollies and the catfish got along just fine. Then the female molly got aggressive with the male molly forcing him into hiding, and chasing him if he came out. This was around a week after she gave birth and I removed the fry.
About a week after the chasing they got along again and I noticed some dark spots that seemed to run under the female molly's scales, by her eyes.
Suddenly yesterday (about two more weeks later) I noticed that the female molly was lethargic and sideways at the bottom of the tank. The top of her is completely dark beneath her scales and it seems to have spread to the male. Both fish have been rubbing themselves on the inside of one of the decorations in the tank, enough to rub the enamel paint stuff from the side of it.
I have had issues with ammonia in my 10 gallon tank and have taken it down to start from scratch as I had too much gravel and was overfeeding for this length of time that the gravel was embedded in slime. (new gravel, new water, addition of air stones and live plants - hopefully to grow sufficient good bacteria!)
Now my fish are separated. The male molly in a 1 gallon tank, the catfish in another 1 gallon tank and the female who barely moves and breathes heavy not eating in a "sick bowl".
I am not sure if the fish have Ich or ammonia poisoning or maybe something else. I have included pics for your analysis.
<Only you can do this. READ here: http://www.wetwebmedia.com/FWSubWebIndex/mollies.htm
and the linked files above. Bob Fenner>
Thank you sooooo much!

Sick Molly? 10/25/11
Sick Molly? (RMF, anything to add/refute?)<<Nope>>

Hi WWM Crew,
I'm new to the hobby, and at a complete loss. I've Googled as much as humanly possible, but lacking the proper terminology can make things tricky. I believe my Molly may be sick -- perhaps constipation, dropsy or a tumor?
First, I'll start with the (hopefully) relevant parameters:
Aquarium: 29 Gallons
Filter: Rena Filstar XP3 w/ 2L Ehfisubstrat Pro
PH: ~8.0
Ammonia[*]: <0.25 ppm
Nitrite: 0 ppm
Nitrate: <5 ppm
Temp: 27 C
Salinity: ~1.004 sg
<Sounds a good aquarium for Mollies. While ammonia is toxic, even at slight concentrations, Mollies don't seem particularly sensitive to ammonia when maintained in brackish or marine conditions, hence their (largely historic) usage in maturing new marine tanks before true marine species are added.>
[*] We triggered what I believe to be a mini-cycle last weekend when we added three new tankmates to the aquarium. Previously, the tank was fishless cycled using bottled ammonia (4 ppm per day) until the ammonia and nitrite levels dropped to zero and nitrates were present. We then completed a ~75% water change to lower the nitrates. The first three fish were then added, and I checked the parameters daily. Now that we experience nonzero ammonia, we change about 25-40% of the water daily until the ammonia drops below 0.25 ppm, with one exception: an Ick treatment** (the new tankmates came with friends!) where I could only change the water every other day. During this, I dosed the tank daily with Prime to detoxify any ammonia.
** API Super Ick Cure Liquid
Presently, there are six Mollies inhabiting the tank. Only one shows signs of this sickness so far. The first thing we tried was to administer the correct dosage of ParaGuard -- which, according to the info, appeared to be a cure-all for the inexperienced like us (antibacterial, anti-parasite, fungicide, etc.). It did not appear to help.
<Indeed. While Paraguard is a good medication, it won't cure everything, and is primarily useful for treating external bacteria, parasites and fungi. It will be of little to no value when treating internal ("systemic") infections. There are essentially two sorts of medicines in the world.
Those that kill pathogens on the outside of the fish, and so work best added to the water *and* dosed to the size of the aquarium; and those that kill pathogens inside the fish, and these work best when administered via food or injections *and* dosed for the size (weight) of the fish. There's little overlap between the two, and on the whole, aquarists can expect good results from the external medicines because dosing to the size of the tank is easy. Medicines that treat internal infections are much, MUCH less reliable because aquarists can't judge the right dose, and a one-size-fits-all approach simply doesn't work. When fish are sick with something systemic, it really makes a HUGE difference getting a vet
involved because a vet can judge the right amount of medicine for the size of the fish, and if necessary, inject that dose into the fish. The worst situation is treating an internal infection with a medicine that is dosed by the size of the tank -- this is unlikely to be the right dose for a fish of given size -- imagine an Oscar and a Neon both in 50 gallon hospital tanks -- which would need more medicine?
The Molly in question has a bulge behind her right gill, which is increasing in size. Her scales in this area are also beginning to protrude. Thinking it was constipation, we have been feeding the fish peas and spinach for the past two days (they generally get spirulina wafers twice daily*, and livebearer flakes once daily** with random greenery substitutions throughout the week). This Molly maintains her appetite, and
does poop, if not as much as some of her tankmates.
* Nutrafin Max Spirulina Meal Tablets
** Nutrafin Max Livebearer Flakes + Freeze Dried Tubifex Worms However, during non-feeding time, she is somewhat active, but appears to "gulp" constantly as if she was trying to eat or breathe and generally hangs out near the middle-to-bottom of the tank. The gulping is really nonstop.
Sometimes, she swims almost 90 degrees vertical, triggered when the other fish pass by.
Thank you for your help!
PS: Pictures attached. Sorry for the quality, they tend to be fast little buggers! :)
<Mollies are of variable quality these days, and systemic infections that cause bloating and dropsy are common. Maintaining them properly helps prevent problems, but once the bacteria or Protozoans multiply sufficiently to cause severe stress, like this poor chap, then there's little you can.
One possibility is Camallanus worms, these are common among livebearers.
But they're distinctive in revealing themselves as little red threads at the anus; have you seen any of these? Shimmies is another common problem, and apparently neurological. It tends to be untreatable directly, but goes away when Mollies are moved into the right environmental conditions. My gut feeling here is that this Molly has something like a Mycobacteria infection, and even with veterinarian help, it would be unlikely to recover. I've seen this from time to time with livebearers, including my own, and tends to happen when fish are past middle age and, crucially, I haven't given them the very best care, so the tank is overstocked, oxygenation is a bit low, the water hasn't been changed much, or summertime temperatures have been excessively high. Euthanasia is usually the best step forward.
Cheers, Neale.>

Re: Sick Molly? (RMF, anything to add/refute?) <<Nothing>> 10/27/11
Hi Neale,
Thanks so much for the prompt and informative reply.
<Glad to help.>
I took the sick molly to a vet after work today, and he confirmed your suspicions -- Mycobacteria -- and euthanized the fish for us.
<Too bad. Sadly not uncommon with this species, and livebearers in general (esp. Platies and Guppies).>
I wish we could have done more, but I think it was the humane choice?
<No question at all. With fish, there's often a very narrow period of time during which you can treat successfully, especially with small fish. Often a few days. If you miss that window of opportunity, your best bet is often to euthanise the fish, then go back to the aquarium and see what the problem might have been. Fix them, then let the tank settle for at least 4 weeks before you add any more fish.>
We had purchased this particular fish three days ago, so it was suggested that it was probably ill before we even got it home.
<Oh, I agree. Mycobacteria infections take longer than 3 days to get to this point. They likely incubate for a few weeks before overwhelming the fish's immune system.>
I realize that you are likely busy with other aquatic crises, but if you have the time, could you verify that we are raising them in as close-to-ideal conditions as possible?
<Are you talking about Mollies? The key things are water chemistry and water quality. Water chemistry needs to be hard and alkaline, the harder the better. If you're just keeping Mollies -- the ideal situation -- then try using the Rift Valley salt mix described in the article below. Even at half the dose, you should find life a lot easier.
At full dose, you will have to limit tankmates to hard water species, so you might decide to go with brackish conditions instead, adding anything between 6-9 grammes of marine salt mix per litre, the lower end if you have live plants. In such conditions you can add brackish tankmates such as Knight Gobies or Violet Gobies. Next up, water quality. Ammonia and nitrite must be zero, and nitrate as close to zero as possible, less than 20 mg/l certainly. In brackish water, the presence of salt actually makes nitrite and nitrate less toxic, so this issue isn't quite so critical. In short, your aquarium seems about right to me, and if your Mollies are otherwise healthy, I'd put this death down to bad luck. Wait, see what happens, and don't add anything else for a month.>
Being newbies, we purchased and configured everything as described on WWM; the "truth about mollies" article you wrote was particularly informative!
Truly appreciated,
<Mollies are lovely fish, and once established, easily justify the extra care they need. Do keep your eyes peeled for Giant Sailfin Mollies. The males comfortably fill a man's hand, and the females can reach 15 cm/6 inches! There's also Liberty Mollies, some of the prettiest fish in the hobby, and actually quite hardy, but sadly also rather nippy, so best kept as a single-species set-up. Cheers, Neale.>

Mollies.... hlth. 10/21/11
A month before I bought home 2 pairs of black and orange mollies. As soon as I reach home male black molly died. After a week female orange molly died. 2 days later the black female molly gives birth to 10 fries. And soon after it too died. now remaining orange male is alive. Comparing to others it is very energetic on those days. But these few days it become dull and remain in bottom of the tank without swimming. I thought that its because loneliness and bought 6 fishes with 4 female and 2 male. but it is in the same condition. please help me to recover my little orangy......
<Greetings. Do read here:
Mollies need a big aquarium, excellent water quality, middling to high temperature, and hard, alkaline water chemistry. Ideally, add 3-6 grammes marine aquarium salt per litre of water. Without the salt, they tend to be delicate. The Molly that isn't swimming much is probably stressed, and improving living conditions will help. Cheers, Neale.>

Sick male molly, possible constipation 9/20/22
Hello. I have been searching this website and the Internet in general for the past 5 days and have not found a definitive answer to my problem. So, I hope that you can help me because I am at my wits end at what I need to be doing. First of all, let me tell you about my setup. I have 1 pregnant platy, 1 albino catfish, 1 Plecostomus, 2 black female mollies, 3 orange lyre tail mollies (1 male, 2 female) and 3 silver mollies (1 male and 2 females). They were in a 20 gallon which I have upgraded to a 55 gallon tank a week ago (both tanks are cycled). Water parameters are Nitrates 20 ppm (as this is what my tap water tests);
<Wow... I would be using RO technology for your potable needs... And look into means of lowering in your systems (posted on WWM)>
nitrites 0, ammonia 0, total alkalinity 120, pH 7.8, chlorine 0, SG in each tank is 1.004. I don't want to add too much salt as I know platys don't like as much salt as my mollies do but I may need to add more?. I have crushed coral in the bottom of each tank as my well water was very soft and this has helped tremendously. These parameters are the same for both my 55 gallon and my 20 gallon tanks. I now use the 20 gallon as my hospital tank. The temp in my 55 gallon is 80 degrees F (and well oxygenated due to the higher temp and tank size) and in my 20 gallon 82 degrees F.
<I'd set these to the mid 70's F.>
I use Aqua-Tech filtration appropriate size for each aquarium. The fish in question here is my male silver molly. I noticed 5 days ago, he was swimming erratically, nose down and sometimes swimming on his side. He seems to struggle to get to the bottom of the tank, primarily floating at the top and looks somewhat bloated. For the past 4 days, he has been isolated in the 20 gallon previously mentioned where I actually have Epsom salt at a ratio of ½ tsp per gallon for reverse osmosis in hopes that will help with the buoyancy some. From information I have read, my best guess is that he has swim bladder problems caused by constipation. My fish diet primarily consists of Tetra tropical flakes and the occasional algae wafer. However, for the past 4 days, he has not been eating at all when previously he had a great appetite. I have tried giving him (cooked and skinned) frozen peas, chopped into bite size pieces to help with possible constipation but he shows absolutely no interest in the peas and will not eat. He seems to be swimming a little better today (day 4 of isolation) but is still not eating and no poop seen for at least 4 days. I try to get him to eat a pea everyday but to no avail. How long can this little guy go without eating?
<Days to a few weeks>
I am afraid he will starve to death. Is there anything else I should be doing?
<Am I to understand the twenty has only RO water and salt in it? I'd add at least a bit of Neale's "Rift" mixture... Here: http://wetwebmedia.com/FWSubWebIndex/RiftVlySaltMixF.htm
Please help. I am still fairly new to fish keeping (approx 2 1/2 months). I am now feeding all of my fish a more variety diet including fresh greens and more algae, bloodworm's once every week or two in hopes of better health. Thanks so much, Anita
<Your note reveals you to be intelligent and caring... I do hope your fish recovers. Bob Fenner>
Re: re: Sick male molly, possible constipation 9/25/11

Hello. Sorry it has taken me a while to write back. Just an update to tell you about. About 2 days after I wrote you my silver male molly finally had a BM! YEAH! I was really getting worried about that little guy. He had a bowel movement each day since. He has been moved back to the main aquarium 2 days ago and doing well. He is starting to get his appetite back and swimming normally and socializing more every day. (He no longer looks like his nose is weighted down.)
<Ah, good>
I am so relieved. I have not used any RO water in either of my tanks. I have looked into the technology but it is not within my means right now. I am going to try to use a different water source for water changes to dilute the nitrates. All of my fish are happy, healthy creatures and I think they enjoy watching me just as much as I enjoy watching them. Thank you for all your help/advise. It is greatly appreciated. Anita
<Thank you for this follow-up Anita. BobF>

Mollies and Cory Catfish... hlth. 9/19/11
I have a 10 gallon tank with 3 Cory catfish, 2 platys, and 2 female golden balloon mollies. I just got the mollies about 3 weeks ago. I've had the Corys for about 6 months and the platys for about 3 months. The mollies developed a white-ish film over the top of their heads between their eyes, it almost looks like their scales are flaking? From researching on the web, it looks closest to Columnaris, but it's hard to tell since I am inexperienced with fish diseases. I removed them from my tank and put them in a 2 gallon beta bowl. Since Columnaris is a bacterial infection(?), I've been putting 2 drops of Melafix in their water. I realize it's not an antibiotic and it's more of a preventative measure, but it seems to reduce the white-ish flaking appearance. I'm trying to figure out what else I could do for them. I know they need a filter for their separate bowl, but I'm also trying to figure out when I put them back in my 10 gallon tank with the other fish, should I put salt in the water? I know Corys are sensitive to it.. Currently, my mollies are swimming normally.. no clamped fins or erratic swimming or lethargic swimming.. If they do have Columnaris, is it contagious to my other fish?
Also, there was a 12-hour power outage about a week ago. I'm not really sure if this is related to that. I don't have an battery operated tank equipment, so they went without a filter and bubbler for 12 hours. All of my fish are very active and I haven't noticed any differences in their behavior (except the Corys swimming quickly to the surface, as if eating the air.. but that's when I added the bubbler). Although since this thing with the mollies, my albino Cory is continuously swimming vertically at the surface. He creates bubbles. I'm not sure what's going on with him.
Thank you,
<Hello Jessica. Your aquarium is too small for Mollies, and the water chemistry you have is won't be ideal for Mollies. As you hopefully realise, Mollies must have hard, alkaline water (which Corydoras will tolerate, but don't enjoy) and are actually easier to keep in slightly brackish water (which Corydoras won't tolerate at all). Melafix has little practical value here, and adding salt at a level Corydoras will tolerate (in the short term, at least) won't reduce the bacterial and fungal infections Mollies suffer from. Do read here:
Treatment for Columnaris is as per Finrot, and needs to be prompt. It isn't contagious as such, though any stressed fish can catch either infection.
Mollies are very common sufferers, typically where water is too soft or nitrate levels too high. Cheers, Neale.>

thank you and help. Mainly Molly hlth. 8/29/11
Hello everyone-
I made some really rookie mistakes, some of which have not been corrected yet, but if you can help me anyway that would be great. For starters, I bought a 5 gallon tank for my children and was advised (incorrectly I have now learned) that we would be fine putting 3 Mollies and a Platy in the tank would be fine.
I was good for a little while, but began getting illness in the tank, Ick. My ammonia levels obviously spiked as well. After a lot of bad advice, adding ammonia reducers, etc., I on my own decided to get a bigger tank hoping it would help. Unfortunately had not been on your site yet to realize I should have gotten even bigger. I bought a 10 gallon tank (if I had read your site would have bought a 20 gallon), 2-3 weeks ago now, added live plants. My male black Molly developed what I thought was Ick, so I removed him immediately from the tank and put him in the old 5 gal and before started treatment, I noticed what I think is fungus.
<Usually such symptoms are promulgated by environmental issues... ammonia exposure, a lack of hard, alkaline water qualities>
He had some puffy stuff coming off his body, along with the spots. Unfortunately I was guided by major pet retailer, and I started Ick treatment. The following day, one of the other Mollies in my tank got the spots on her fins, so I removed her and put her in the old tank. The black molly was much improved, but still had a white mouth and cloudy eye. At some point, the female molly still in my big tank had babies and I was afraid to treat the big tank.
Now, my Platy turned up with what looked like parasites on it, long, white strings coming off the body.
<Yikes... likely Anchorworm. Please read here re:
I removed him also and put it in the sick tank. Again, went to major retailer for advice. I started fungal treatment on the sick tank. All the fish in the sick tank looked beautiful, mother Molly started with the white spots at night, so I removed her. I know I should have gotten the baby out and treated the tank, but I have two young boys and I didn't want them to be disappointed if the fry didn't make it, they didn't even know they were there. After a few days, all the fry died.
The ammonia and nitrate levels in the 10 gallon tank were dangerously high but the sick tank was ok.

I went back to the fish store, got advice and started again. I put the fish back in the big tank, put an ammonia treatment in the tank
<These only work at the immediate moment... won't solve uncycled, under-filtered, over/ and mis-fed system issues>
and started medicine called Lifeguard which is supposed to treat viral and bacterial problems.
<The real issue/cause of trouble here is the environment...>

This required removing the charcoal filter. After 2 days, my usually very active Mollies where in bad shape, hanging at the top of the tank, not eating, one was just rocking side to side. It was late at night, so I just used my intuition that they weren't getting enough oxygen, so I put a second filter on the tank, got a bubbler set up in the tank and put the carbon filter back in the tank. The two black mollies seemed improved before bed but the third still not so good. I literally put the bubbler under her body (since she wasn't moving), went to bed and hoped they would be alive when I woke up.
The next day I found your site. Two of three mollies were doing much better, swimming a little but still at the top, eating. The third, moving around the top of the tank but not eating, the Platy much improved. All water levels were normal now. I have never added salt to the aquarium but after doing research on your site decided to try it.
I did a 30% water change and since I have a mix of Mollies and a Platy, and if I understood everything, they prefer different water, I only added 5T of salt.
<Good; both can tolerate>
I got a heater and set it at 78 to keep the temp more stable, bought a long bubbler rock, and added some natural liquid biological stuff. In the afternoon all fish seemed much better! I fed them some cooked, peeled peas and my third molly started eating. After 4 days, all the fish were completely normal appearing, the third molly actually has a beautiful sheen to her body.
Day 5, I still have normal water chemistry, looks great, but my black female molly (who is pregnant again) appears to have the beginning of some white around her mouth?
<Don't panic! Nor treat>
It is barely noticeable and I can't get a picture of it.
I had stopped all the medicine as I stated above after 2 days on a recommended 5 day dosage. I am terrified after bringing all these fish back to live, they may perish anyway! I hate to treat an unknown disease or a paranoid owner disease, but I don't know if I should do something.
<Keep monitoring water quality and reading! Cheers, Bob Fenner>
Re: thank you and help, FW 8/30/11

Thank you so much. Still watching, not much change so maybe I am just paranoid now.
<Mmm. B>

Molly hlth. rdg. 8/19/11
I have a black Molly male who has just healed from Dropsy. I noticed a white sore over his right fin. It seems to be oozing. I have him in a small hospital tank
<Not a good idea to place Mollies in small volumes. They are very sensitive to poor water issues>

to treat the Dropsy and was about to put him back in the big tank when I noticed it. I do not think this is Ick. It's about the size of his eye and oozes white stuff. I have cleaned this small tank twice in a week. What else can I do?
<Read here: http://wetwebmedia.com/FWSubWebIndex/MollyHlthF8.htm
and the linked files above... Bob Fenner>
Kerri Dufrene

Molly Question... 8/4/11
I have read through many of the molly postings that are on your site. I, however, did not see anything that went along with my "issue". I have a tank with a variety of fish, mostly mollies. I have had several issues that I have worked through (the biggest issue being an ammonia problem - fixed now, but was scary). I clean the tank regularly and now have added a UV Sterilizer.
<Do understand what these are for, and critically, their limitations.
Retailers sometimes overstate their abilities.>
I noticed a couple weeks ago that my one orange molly has a black "outline" on its tail fin and in the last few days a grayish / ashy looking spot on his head. He swims normally, his scales do not seem to be any different from the others in the tank, he eats, his eyes look fine, there are no black spots just this line and discolored area. I can't seem to find anything online regarding this. Is it possible for mollies to change colors or develop normal color variations after you have them for a while?
He was completely orange when we got him. I am utterly clueless and just want to make sure if this is really a reason for concern or no big deal at all.
<Very hard to say.>
My water conditions are all ideal.
<Meaning? Do need some values here.>

As stated I do weekly water changes / gravel vacuuming. I test my water every few days with multi-purpose test strips and if any of the colors seem a little off I double check with my full test kit (and if nothing is off, I still run full kit test once a week).
Any information is much appreciated. I have attached a couple pictures for you to have a better idea of what I am talking about. Unfortunately, he was too fast for me to get a good picture of his face/head.
Thank you,
<Do not think this is a disease as such. Could be genetic, or nerve damage, which oddly enough can cause weird colour changes on fish. For now, observe, and continue to provide the best possible conditions for your Mollies: hard, alkaline, warm, and preferably slightly brackish water conditions. Cheers, Neale.>

Re: Molly Question... 8/4/11
Thank you for such a quick response.
<Glad to help.>
1.) UV Sterilizer: I purchased this mainly for a water clarifier due to some serious cloudy water issues. I had water clarity issues after I got all of the ammonia under control. I reduced the time the light was on, adjusted feeding amounts, cleaned all but one small item in the tank (as read online, that maybe my tank may be "too clean") and nothing worked. I had read online all about the UV Sterilizers and purchased for its ability to "fix" my water clarity. I understand a good bit of the other benefits it may hold, but even if it only cleaned the water so it were clear, it (in my opinion after my excess of frustration) is a good investment for $50.
<Yes, would agree, these UV sterilisers can be a good way to deal with diatom blooms. Less useful for bacterial blooms.>
2.) Water Conditions: My water is hard, Chlorine is 0, PH is 6.8,
<Too acidic for livebearers, which really need around pH 7.5, if not slightly higher.>
Ammonia is between (today / 2 days before water change) 0.00 and 0.25ppm,
<This amount of ammonia is slightly worrying; it should be 0 in a well-filtered and maintained tank. Ammonia is a serious stress factor on Mollies especially.>
Nitrite 0.0ppm, Nitrate 0.0ppm and Alkalinity is between the 40 and 80 mark on the scale'¦
<Fine for most fish, but do beware that Mollies are more sensitive to most, especially in freshwater.>
Water temp is between 75 and 76 degrees.
<Acceptable for low-end tropicals like Platies and indeed most tetras and Corydoras, but slightly cool for fancy Mollies and other species that need lots of warmth.>
- I don't think (from what I have read online) that I can do brackish water since I have tetras as well... Is this correct?
<For the most part, yes, this is correct.>
I have added a small amount of aquarium salt that (per the directions) should be a safe amount for all fish to be happy.
<This salt will provide a marginal benefit, at best, but may stress the salt-intolerant fish like most tetras. The routine addition of salt to aquaria is now deemed to be at best pointless and at worst harmful, so you'll find no modern aquarium book recommends it. It's a hangover from the hobby up to about 1970 when people kept robust, salt-tolerant species that were less harmed by the salt than they were by poor water quality. Salt slightly reduces the toxicity of nitrate and nitrite, hence the benefit.>
Is there anything else I can be or should be doing differently (not only for this fish, but for the longevity and happiness of all my fish)?
<Do read; starting here:
I have Tetras, Platies, Mollies, Gouramis and Betta (1 male 2 female).
Thank you once more.
<Always happy to help. Cheers, Neale.>

Balloon Belly Molly problem 7/16/11
Hi! I have been reading your info forever, now I need your help!
I will attempt to describe the issue as well as possible. I've had balloon bellied mollies for 8 years and I'm stumped I purchased this BBM over a year ago, she was a light gray and white mix, full size and seemingly healthy. I never had a problem with her. She had a couple sets of fry within the first few months I had her and she and her fry did well and were healthy. Shortly after I removed the males from that tank and there were no more fry from her. In the past 6 months she's been... Changing. She is now twice the size of all my other bbm's, and her front half has turned orange.
Vivid orange. But the back half of her is still this gray white color. The scales on the orange half are large and almost look like they bubble.
<I see this in your photos>
Lately I've noticed she'll get a hole through this area (almost thought it was an ulcer) but it doesn't seem to bother her and it'll heal up and then I'll notice another. But she is not bloated or just swollen. She has actually grown. Example- her mouth is twice as large as the other fish. She could eat one of my frogs' crickets if she wanted! I've researched everything. It's not a tumor. It's not hole in head disease. I can't figure it out. She honestly looks... Old. My water levels are great and none of my other fish have problems. And she is still as energetic as always. Eats well. Sometimes I wonder if she's going blind though. Anyhow. Her body looks like the front half belongs to a different fish. Changed colors, 'blew up', scales are huge and almost bubbly. They are pineconing on the orange half. Over night last night the top 'irregular' half of her has started to turn pinkish white and her scales look like a finger that's been in the water way to long. Hoping you can help! I have included some cell phone pictures, sorry for the quality. Thanks!
Taryn Phillips
<This looks to me like some sort of "Elephant man/fish" syndrome. A genetic anomaly. Do any of this fish's young show these traits?
Bob Fenner>

"I am elephant molly fish"

Re: Balloon Belly Molly problem 7/17/11
Thanks for the quick reply!
<Thank you for sending in such an interesting post Taryn>
To answer your question, no, none of her fry are showing signs of this. The ones that are still in my care are beautiful white with very well shaped bellies.
<Ahh, more weight to the thought that this is a genetic anomaly>
However at about 8 months old now they are not quite the size of my other adult Balloon Bellies, but I have noticed they are still growing. I have wondered about some sort of Elaphantitis,
<Mmm, well, this condition is mainly caused by Nematodes... a type of filariaisis, blockage of circulation... I suspect summat else here w/ your mollies>
and it maybe be something that will show up in her fry in a couple years. I had a recommendation to take her to a biology or zoology lab at a local university after her passing. What are your thoughts on this?
<A good idea in my estimation. This "strain" might prove of some good use in study. BobF>

Molly really sick?! 6/17/11
I have three female Dalmatian Lyretail Mollies in my tank. The temperature is right, pretty much everything is good.
<... need values, not opinions to help you>
However, after one of my females was pregnant and had the lil' fishes, she started acting really weird. She began swimming vertically with her head up and tail down.
<Not good>
Now she refuses to eat, she is insanely thin, and stopped swimming around. My other fish
<Which are?>
are perfectly normal and I found out my other fish was also pregnant, and completely happy. At one point I walked into my room and found that sick fish stuck to the filter, nothing was the matter besides how weak she was.
I am really worried that she is going to die, and I don't know what it is.
I put her in a separate 10 g. tank for now. Thanks.:)
<... Please read here: http://wetwebmedia.com/FWSubWebIndex/mollies.htm
and the linked files above. Most folks don't realize how hard Mollienesia are to keep; that they can't be kept w/ most other "community" fishes. Bob Fenner>

Dalmatian Molly Problem 6/5/2011
I have a chocolate and Dalmatian molly as the only fish in a 10 gallon tank. The Dalmatian has given birth once or twice since I've had her (2 years maybe). The fry were moved to a 20 gallon tank.
The Dalmatian has been showing signs of stress over the last month or so - rapid breathing, vertical hovering, and a puckered mouth. The chocolate is asymptomatic. Over the last week, the Dalmatian has started to lose its white areas and turning darker in general.
Do you have any idea of what might be happening and a possible treatment?
Much appreciated.
<Do read here:
Mollies do poorly in small tanks, and they also prefer slightly brackish to freshwater, and soft water especially will cause serious problems. In non-brackish water they are very sensitive to nitrate, and in small tanks especially nitrate levels quickly rise between water changes, causing stress. Cheers, Neale.>

Re: re: tropical fish aquarium...? Molly hlth... 6/3/2011
hello again crew! my black mollies fins are going almost see through. like transparent. is this normal? or does he have fin rot or something? thanks for the info before. tank is doing better already
<Transparent, like cellophane, good; opaque, like rice paper, bad. Fins should be whole and smooth at the edges; fraying or raggedy is bad. White fluffy bits imply fungal infection. White clots can be fin rot; salt-like grains, usually Whitespot. Cheers, Neale.>

Molly, no useful data 5/5/11
My black Molly has been doing fine and I've had it for at least 6 months...
It has begun to grow bubbles on its insides and a white hole by its tail, I have no aggressive fish in my tank (1 platy, 2 male guppies, 2 male cherry barbs and 2 female cherry barbs), at first I thought that it was pregnant but It only hangs out around the heater and the bubbles seem to be getting bigger. I don't know what is wrong with it. Please help!
<... what re water quality, nutrition, the system/set-up? Read here:
and the linked files above; particularly re systems, disease. Bob Fenner>
Re: Molly, no useful data 5/6/11

20 gallons, Aqueon 10 filter, ph 7.4, fed twice daily in the morning its dry flakes and at night its frozen bloodworms
<I'd skip the latter; otherwise nothing "jumps out"... do read where you were referred, and the linked files above. BobF>

Balloon Molly died while giving birth 4/18/11
Hello there,
We have a 47 gallon, tall freshwater fish tank. Inside are (were) 3 adult female balloon molly's, 2 baby balloon molly's that are about 2 months old, and 1 dwarf male Gourami.
<Yikes! Two of the worst species for the casual aquarist. Plus, the water conditions your Mollies need are inimical to what Dwarf Gouramis need. So there's no real likelihood of easily keeping both species healthy in the one aquarium.>
The baby balloon molly's arrived the day after we got our two black ones.
We didn't know what we were doing at that point, but she had 10 babies. 1 was a stillborn, and 7 slowly disappeared as we didn't know about the frequent water changes and our nitrite level suddenly sky rocketed!
<Nitrite, with an "I", as opposed to nitrate with an "a", comes about from poor filtration, not water changes. Understand this: fish excrete ammonia all the time, and then your biological filter processes that to nitrite and finally to nitrate. So in a healthy aquarium you should have zero ammonia and zero nitrite because they're continually being removed, but steadily rising leaves of nitrate because that's the end product of the biological filtration process. Water changes -- 20-25% per week -- dilute the nitrate, and for Mollies in freshwater tanks (which I honestly don't recommend) that nitrate level has to be very low, less than 20 mg/l, and ideally close to zero. In freshwater conditions nitrate is more toxic than in brackish, and Mollies are very sensitive to nitrate, more so than your Gourami, and consequently likely to be harmed by high levels of nitrate. Ammonia and nitrite, by contrast, are dangerous to all fish no matter what the conditions. In the average community tank, levels of 0.5 mg/l ammonia and 1.0 mg/l nitrite are potentially lethal. Anything above zero is definitely not safe. If you don't have zero levels of these two chemicals, then you have either [a] too many fish; [b] too little filtration; or [c] you're feeding them too much. Oftentimes it's a combination of the three.>
We did a couple water changes to get the nitrite level back to about 0 and are feeding them less since we found a great deal of food at the bottom of the tank when cleaning the gravel.
<Nitrite won't be permanently pulled back to zero by water changes because it's continually being produced by your filter as the bacteria process ammonia produced by your fish. It's crucial you understand this. You MUST remedy the problems with your filter and/or reduce the stocking level and/or reduce the amount of food you're giving them.>
Yesterday around 4pm I noticed the third balloon molly, who is orange, suddenly sitting at the bottom of the tank. She had two growths that looked like little bubbles on her behind which made us think she was in labor. We had a male in the tank about a month ago, but died shortly after. We believe he impregnated at least the one. Our heater broke so we had just gotten a new one the other day to keep it at a warmer temperature for the babies especially.
<Mollies are very sensitive to cold water, but so are Gouramis.>
We do not have a breeder net, but the other fish have left the babies alone and it is a large tank for the number of fish inside. (We plan on getting a breeder net for future babies but this wasn't expected right now). After about an hour, the other fish left the orange balloon molly alone. We turned off the light and the temperature in the tank was between 78 and 79 degrees. As of this morning, she still had not had any babies. She would move all over the bottom of the tank and hide a little, but the other fish were not bothering her.
Around noon today I saw the mother was laying on the bottom of the tank, dead. Those two bubble-looking things are still on her bottom, but we have no idea why she died. I tested the water for everything but ammonia (we haven't gotten any new fish in a few weeks and at that point it was only 1),
<1.0 mg/l ammonia isn't something to scoff at! That's pretty dangerous!>

everything came back normal and safe. Nothing was borderline being dangerous or anything like that.
<Really do need the numbers rather than your interpretations. Let's be clear here. Mollies require water hardness upwards of 15 degrees dH, and a pH above 7.5. Water quality must be ammonia = 0, nitrite = 0, and nitrate less than 20 mg/l. Moving on to the Dwarf Gouramis, these need very soft, acidic water, 1-10 degrees dH, pH 6-7. Again, water quality has to be excellent, 0 ammonia and 0 nitrite. I can't think of any middle ground that would be healthy for both Dwarf Gouramis and Mollies, so keeping them in the same tank is bound to be difficult.>
The last water change was done about 4-5 days ago and we were planning on another soon.
Ich is not in the tank and all the fish are acting perfectly normal. Did we do something wrong to cause her to die? We've had her since about February of this year. She was fine up until yesterday when we thought she was going to have her babies.
Thank you for your help.
<Trisha, the bottom line here, I suspect, is you've bought fish that you really don't have the skills or set-up to keep. Mollies are not easy fish to maintain, and many people find them impossible to keep in the long term.
Those are usually people who refuse to set up tanks catering to the needs of Mollies, i.e., hard, alkaline, and ideally slightly brackish water. Of course adding salt isn't an option here because salt would stress your Dwarf Gourami, and they're flimsy enough already without being stressed further. Do help yourself by doing some more reading, and pay particular attention to the needs of Mollies and Dwarf Gouramis, and the proper way to set-up and maintain an aquarium.
Hope this helps and good luck, Neale>

Sick Dalmatian Molly? 3/30/11
<Hello Denise,>
I need help with my Dalmatian molly. I'm new at this, and my 56 gallon tank is only two weeks old.
<Still cycling; fish will not be safe until well after 6 weeks of the tank being cycled. Ideally, this is done before adding the fish, using a source of ammonia such as daily small pinches of flake food.>
Have had 5 fish for 5 days, all was fine yesterday, but today the molly has been sitting at the top, in one spot all day. I have an air pump,
<And a filter, I hope.>
and also did a 25% water change. Water has been dechlorinated, and bacteria supplement added.
<What sort of supplement? Why?>
Temperature around 77. Tank mates, two gouramis, 1 cremecicle lyretail, 1 tetra.
<Tetras and Mollies require much different conditions, and make poor choices for life together. Plus, Tetras are invariably schooling fish. Take it back to the shop if you can.>
The Dalmatian is still eating, and looks normal, but won't move from the top of the tank in the corner, and up to this point was very active. Seems like it's having trouble getting oxygen now? The other 4 fish are fine.
What am I doing wrong, and what can I do to help him/her?
<Do read the needs of Mollies, plus cycling tanks.>
Thanks in advance for your help.
<Start here:
All will be revealed! Likely poor environmental conditions, plus the wrong water chemistry for the Molly, will be the root cause. Fixing will simply require you to correct these conditions. Cheers, Neale.>

Question: Mollies/GloFish Dying 2/23/11
Hi WWM crew,
<Hey Jace>
I've got a question regarding the general health of my aquarium. About a month ago, I completed cycling my 55 gallon aquarium and added 3 black mollies (1M 2F) while I decided on the other tankmates that I wanted. Since then I have added 3 sunburst platys (again 1M 2F), 8 male guppies, 6 GloFish, and 10 ghost shrimp. My tank is moderately planted with plenty of rocks and other constructs and the substrate is a smooth gravel. My water is at 76F, about 7.8 PH, 0 ammonia, 0 nitrite, and about 5ppm nitrate.
While one of my platys has recently given birth to some fry (unsure how many... removed one shelter to clean it today to discover a few baby fry, most of which became a snack before I could move them somewhere safe), I have lost two GloFish that had no visible problems but had been swimming deeper than usual. I also lost one molly after it had developed a kink in its back and had difficulty swimming -- its tail frequently drooped and it swam with its head very far up. I could not seem to get it to eat and its excrement had become a translucent white and seemed to come out much slower than normal. My second female molly is now keeping close to my water heater right at the surface, in a similar behavior to the now deceased female, but does not appear to have the other issues.
<Mmm, what species of molly is this? Can you look into its recent water quality (from/through your dealer)... They may well have been kept in "saline" conditions. Please read here:
and the linked FAQs files above re Systems and Disease>
Should I be thinking about some sort of fungus, bacteria, or parasite treatment here? I'm a new aquarist and don't know quite what to do when the water appears to be fine.
<Do read for now. Bob Fenner>
Re: Question: Mollies/GloFish Dying - 2/23/2011

Thanks for the response. They are black mollies -- I'm afraid I don't know any more than that, though the link that you gave me makes me believe it to be Poecilia latipinna (text later reads Poecilia hybrid).
When I purchased the fish I was told they were kept in slightly saline conditions and to add one tablespoon of aquarium salt to each five gallons of water, which I have been doing. I don't know the specific DH for my water, but I do know that my location is notorious for hard tap water (my tank is showing the lime deposits from evaporation to prove it).
<Mmm, well... as you are likely aware (now), this genus has many issues as captives. Nothing from the information you presented "jumps out" as a/the likely source of mortality... GloFish as well are poor shippers... It may be that you just have "too stressed" specimens here. BobF>
Re: Question: Mollies/GloFish Dying 3/4/11
To follow-up, I have since lost a fancy guppy and another female black molly is exhibiting this "kink" in its back.
<Mmm, unusual... as with such in humans, these conditions are genetic/developmental, nutrition, injury/trauma and at times, pathogen-related>

What once were lively, fine fish a few weeks ago have this kink seemingly appear overnight. I've included a picture of this fish. Thinking it may be some sort of infection/parasite, I gradually increased water temperature to 80 degrees and bit of extra salt to the tank. I have continued to check water quality and it is consistently 0 ammonia and nitrite, 5-10ppm nitrate, PH 7.8-8.0. After reading around on your site, I have read that one cause of bent spines is Mycobacterium marinum. I am a college student with not a lot of money and not a lot of space and I don't have a hospital tank -- the only other thing remotely close to this hobby is a 1 gallon fish bowl. Thoughts on where to go from here?
<Considering your present circumstances, I'd leave all as is, not "treat", and not raise the temperature beyond the 80 F. Bob Fenner>

re: Question: Mollies/GloFish Dying 3/4/11
Lost the two black mollies overnight. Glancing about my tank, I noticed that those fish that passed as well as some others that visibly look normal all have that milky white, stringy feces I mentioned -- it's typically almost hairlike in diameter with thicker white beads every so often. I have noticed that while my fish used to easily pass either pink or green feces (the color of the protein or algae flakes they ate), almost none of them have feces of that color. The mollies especially had a white anus. Many of the fish that swam energetically in schools, like the guppies, now spent most of their time in the corner or by the heater.
<... you might want to look at their fecal material under a 'scope. Perhaps Hexamita/Octomita. B>

Sick Molly Fry? 2/4/11
Hi Neale/WWMC,
I have 8 black Molly fry about 8 weeks old. The 4 largest have gills that stick out. It actually looks like the white lining of their gills are sticking out. Their gills are not red. They show no other sign of being sick/stressed etc.
<Yes, I think this is simply a birth defect -- missing or shortened gill covers, so the gill membrane and/or gills themselves become visible. Not uncommon with Mollies and other livebearers because they tend to be inbred: people buy a brother/sister pair from a pet shop, they breed them, and then those are taken to a shop, and someone else buys a pair from that batch of siblings'¦ and so on.>

They eat normally, swim healthily, have no other marks or abrasions and do not rub their sides/Gills on rocks or driftwood.
It's like the inside of their gills grew bigger then they should have.
They're a white/grey color.
Have you come across this before?
Because I have searched high and low and can't find a similar case. No picture I've seen resembles this. I've tried to get a picture but they're so small as is, it's hard to get a pic. Doesn't look like gill disease, doesn't spread like fungus, doesn't look like parasites.
Any suggestions? Any idea of what this could be?
My tank is slightly brackish 1.002
Ammonia, nitrate, nitrite all at 0
Water is hard above 8.
Shouldn't these be ideal water conditions for Mollies?
I do a 20% water change each week. Sometimes a little more even!
Any input would be great thanks!
<If they're fine, you might leave things be. Or you might elect to destroy humanely any deformed ones -- 30 drops of clove oil in a litre of aquarium water will do this very quickly. That way any that remain and breed should at least lack this deformity. Try adding another Molly from another shop to the mix -- often this perks up the gene pool dramatically, and you get much better fry. Cheers, Neale.>

Ammonia levels and Molly trouble. 12/30/10
I've got a couple of questions regarding a new tank.
<Okay. Start here:
I bought a 10 gallon (48 litre) tank two and a half weeks ago. I bought it from one of a chain of large pet stores (my first mistake)
<A bit unfair. Large chains can be just fine, but as with *any* purchase you'll do best if you do your research independently. By all means take advantage of low prices and wide ranges of stock, but *know* what you're buying.>
and thought that asking them a million questions would be better research than reading (my second mistake.)
<Indeed. Do buy at least one aquarium book. Many good titles can be obtained used from Amazon.com and similar, not to mention your public library.
On their advice, I set the tank up with heater (24 degrees C), filter, gravel and decorations, and had it running for three days.
I went back to the store to buy my first fish. I asked for lots of advice and came away with a Corydora catfish,
<Singular of Corydoras is Corydoras. It's a scientific name, Corydoras, e.g., Corydoras paleatus, rather than a plural.>
a black Molly, a silver Molly, and two Dalmatian Mollies.
<These Mollies need at least 20 gallons, and I'd strongly recommend 30+ gallons.>
The Cory died within an hour and was replaced after having my water tested.
The water was apparently perfect, but they said to change my temperature to match theirs (26 degrees C.) I changed it by one degree so I didn't shock them, but three Mollies died overnight leaving the black Molly (female).
The temperature in my tank is now 26 degrees.
I went back to the shop in tears, and was told that my water was too acidic.
<Indeed. Mollies require hard, basic water. This has nothing really to do with pH, though the pH should be around 7.5 to 8.5. What makes or breaks your Mollies is the hardness. Mollies either need water that has been strongly hardened using a Rift Valley salt mix at 50-100% the recommended dose, or else slightly brackish water, with 5-10 grammes of marine aquarium salt mix per litre. For beginners, adding 5 grammes of marine aquarium salt mix per litre is BY FAR the easiest way to keep Mollies. Do read:

Needless to say, Mollies aren't good companions for fish from acidic water conditions like Corydoras. Instead, keep them on their own, or mix with salt-tolerant species or brackish water species, such as Knight Gobies and Brown Hoplo Catfish.>
Through several water changes I got the ph to 7.6 and the pet shop said I could put more fish in. I got another Cory and another black Mollie as I'd learnt that they are shoaling fish.
<Mollies aren't schooling fish. Males are very aggressive. Keep at least two females per male.>

Cory's one and two are both fine, but Molly 2 was very weak and I'll looking when introduced to the tank and Molly 1 wouldn't leave her alone, and she too died overnight.
After all this, we finally found a family run local pet shop and bought two blue tetras. They took a few days to settle in, and we've had no problems with them (except for them eating whole catfish pellets!)
<You need more than two Blue Tetras (Boehlkea fredcochui) for them to live for long. They're schooling fish, so keep at least six. They're also very nippy, and will damage slow-moving fish such as Mollies. All this is clearly stated in aquarium books.>
On Christmas day, my Molly gave birth to two babies. These are now five days old and are doing well in a nursery tank floating in the main tank.
<Well, some good news there, at least.>
The adult Mollie is now being extremely aggressive, to the Cory's in particular, and especially when there is food around. The Molly seems to be very hungry all the time, but I've been told not to feed her more than normal. This is my first problem. I need to know why she is being so aggressive, and if it's temporary or not.
<Mollies aren't "nice" fish. They aren't easy to keep and they tend to throw their weight around. Mollies are beautiful, yes, but they aren't fish for beginners. Any good aquarium book should state this.>
My second problem is with the chemicals in my tank. The levels of ammonia and nitrite were low, but nitrate was high, so we bought some plants to help. Since then, my nitrate has dropped to 5ppm, but the ammonia has shot up to 1ppm, and the nitrite to 0.5ppm.
<The rise in ammonia and nitrite imply poor filtration, overfeeding, overstocking, or some combination of the three. Do read:
Do further understand that biological filtration is what you need, not carbon or Zeolite.>
I am changing the water every day, 25 or 50% on alternate days, but this isn't helping! I've used Filter Start since we've had fish to boost the bacteria levels and my tank is spotlessly clean, so I can't figure out where I'm going wrong, or what to do to fix this. Please help!
<Buy, borrow a good aquarium book, curl up with it in the next day or two, and read about keeping fish. It's not hard, but the mistakes you're making are easy ones to fall into without forethought.
Sorry the email is so long, I've had so many different things go wrong and really need to get it fixed!
<Do please read where directed.>
Thank you!
<Hope this helps. Cheers, Neale.>

Problems with my Dalmatian mollies (and I think maybe more that one problem?) 12/27/10
I'm really struggling with my new fish. In the middle of November I set up a new 100L tank. It has gravel, an elite submersible 150W heater set at 26oC, a couple of plastic plants and an Elite jet-flo submersible filter with a zeocarbon cartridge. I added Aqua plus water conditioner and a biological aquarium supplement and let the tank settle for a week before adding 5 sword tails (1 male, 4 females) and 2 silver mollies (one female and one male) and 4 Dalmatian mollies (1 male 3 female). All seemed to be going well. I was instructed to do water changes every couple of weeks, using the same additives in the fresh water. After a couple of weeks one of the female Dalmatian mollies died. I thought nothing of it and put it down to 'one of those things'. However a couple of weeks after that I lost the male silver molly. This fish was ever so skinny and towards the end just lay on its side. It has always been thin so put that down to being ill prior to me buying it. Next I lost the other silver female molly. She has been swimming a bit strange, bouncing off items in the tank like she was rubbing herself. I kept a closer eye on the rest from this point onwards as a few to many were now dying. I've had no issues with the sword tails at all. I stopped adding the biological aquarium supplement at this point and introduced a couple of live plants to see if that would help. A couple of weeks after this (still doing regular water changes and adding the tap water conditioner) I lost the male Dalmatian. This was a shock as I thought he was health. Eating well and very active. I took a water sample to the place I bought the fish who informed me that my nitrites were very high and that they thought I had a fungal infection in the tank. I went back home did a 50% water change adding in the biological aquarium supplement and removing the live plants which seemed to do nothing other than make the tank water murky with lots of plant bits floating around. I treated the remaining fish with Protozin. I bought a test kit and kept and eye on the fish. All seemed well again. I bought another 6 Dalmatian mollies. 2 male and 4 female. I had about 2 weeks without any problems. In fact a week ago I found 5 Dalmatian molly fry in the tank who all seem to be doing really well. However, I lost one of my original Dalmatian molly females last night. Like the male silver molly she was very thin even though I saw her feeding. I constantly test the water the results are always good. The tests last night read pH (7.0), nitrate (<5mg/L), nitrite (<0.1mg/L), NH3 (0mg/L), chlorine (0mg/L), GH (8od ish - dip stick test) and KH (6od ish - dip stick test). I have noticed that one of my new Dalmatian molly females now appears to have a hump just in front of her top fin. It just looks like a generalized swelling from the back of her head to her top fin. She is also swimming a bit erratically at intervals, not all the time. I fear she will dye next. I have started to introduce a bit of aquatic salt (only a bit at a time - I've only added 2 teaspoons) to see if this helps. Do you have any suggestions as to what might be my problem and what I should do? I still have all my sword tails, they seem absolutely fine. Any help would be gratefully received.
<Hello Sarah. Do start by reading here:
Whereas Swordtails are relatively unfussy fish (though they do need to be kept cool, 22-24 C being optimal) Mollies are far more tricky fish to maintain. Exposure to non-zero ammonia and nitrite levels quickly kill them, at least under freshwater conditions, and nitrate levels above 20 mg/l are stressful under freshwater conditions as well. Though some expert aquarists would argue Mollies can be maintained perfectly well in hard, basic freshwater (i.e., 15+ degrees dH, pH 7.5-8.5) it is debatable whether beginners should ever keep them in freshwater conditions. I'd argue Mollies are easier to keep in slightly brackish water, about 5-6 grammes marine salt mix (not tonic or aquarium salt) per litre being very useful. Most sick Molly issues come down to water quality and water chemistry issues.
Review the needs of these fish and act accordingly. Mollies aren't community fish and should not be kept as such. Cheers, Neale.>
Re: Problems with my Dalmatian mollies (and I think maybe more that one problem?) 12/27/10
Thank you ever so much for getting back to me so quickly on the matter and for providing such useful information. Shop owners should be shot for handing out unsuitable matches of fish especially when they had been asked if the fish were compatible. Anyway that's not the issue now. You say that the sword tails are not as fussy. Could the sword tails survive quite happily in the water if it is brackish or even with a higher saline content? Is there a happy (ish) medium for these two fish? Could you recommend a good book that would provide such useful information so that I don't make such hideous errors in the future. I really want to make a go of my tank and the fish.
Thanks again for you very helpful advise
<Yes, Swordtails will thrive in brackish water. Not strongly saline conditions, but salty enough to make a difference for your Mollies. I'd recommend 2-3 grammes marine salt mix per litre of water. That'll be cheap and easy to produce, will be good for your Mollies, and won't harm your plants or filter bacteria. There are numerous other fish that will tolerate such conditions too: glassfish, blue Acara, Horseface loaches, knight gobies, and so on, so adding livestock to this community, should you want to, wouldn't be hard at all. As for books, do have a read here for some favourites:
The Peter Scott "Complete Aquarium" book is particularly good for people wanting to build community tanks and can be picked up for pennies online as a used book. Cheers, Neale.>
Re: Problems with my Dalmatian mollies (and I think maybe more that one problem?)

Your a star. I'll look for the book you suggested and get to work on the water right away. I'm not going to attempt to obtain other fish until I know I can keep the ones I have but it is great news that this is a
possibility for the future.
Thank you ever so much again. Your advice is invaluable.
Kind regards
<Glad to help, Sarah. Cheers, Neale.>

Dying Balloon Mollies, 11/26/10
Good day,
2 months ago I bought 10 small Balloon Mollies. I have a 20 gallon tank with all the proper filters and heaters.
<Too many for this sized tank. See here and related FAQs for more. http://www.wetwebmedia.com/FWSubWebIndex/mollies.htm >
About 1 month after I bought the fish, 2 of the Mollies died. I read some articles on your site and decided to change the water to more brackish water from the fresh water it was and change their flakes to veggie flakes.
<What SG are you running the tank at. What are your other water parameters, ammonia, nitrate, nitrite?>
The last two weeks I have had a Molly die each week. All the water measurements are good and the temp is stable at 28 degrees Celsius. Today a third Molly is looking ill, showing the same symptoms as the two that died. She keeps getting sucked against the filter and her tail seems to be hanging a little limp. She seems really lethargic in general. I now have her in a breeding net to stop her from being sucked up against the filter. I went through the same process with the other two mollies and by what happened to the other, this one will be dead in the next day or two. I really want to find out what it is that I am doing wrong as I am very fond of the fish and would really not want anymore of them to die. The salesperson at the petshop just keeps saying stuff like "it happens" and "sometimes you just get a bad batch", but surely I must be doing something that is making them die.
<With mollies water conditions are almost always the culprit, and the highly inbreed balloon varieties are even more sensitive than the standard fair. Also I would probably try to find a new petshop, they don't seem very helpful.>
I bought three more girls in the last week as the ratio between boys and girls where getting too even, so I now have 4 boys and 5 girls.
Hoping you can help.
Venette (South Africa)
<Are you using marine salt for your brackish conditions? Ultimately you have too many mollies in a relatively small tank, I would not keep more than 5 or so in a 20 gallon tank.>

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