Problems with aquarium

[Comanch]

Hello. I need advice about my aquarium. Mollies in my 120 gallons about two moths ago started to act strangely. They slowly starts to loose ability to control they swimming. And after about two weeks like this, I find them dead. And it seems to effect only 1 or 2 mollies at a time.
This is a link for video with molly swimming:
https://photos.app.goo.gl/jkyB3U344QJHyaXQA

In my aquarium also lives angel fishs, barbs, rasboras, few danious and corydoras, but as far as I notice it only effects mollies. Water changes is done weekly and water parameters seems to be ok. In that time aquarium was treated with JBL Furanol and Sera costapur. But it didn't helped.

Maybe you guys have some advice what it could be and what to use?

 

[SaraB]

Mollies are surprisingly sensitive to bad water conditions.
What are your exact water parameters/ water change schedule?
Is there any chance that they were being picked on?

 

[Comanch]

Hello again. Sorry for long time without replying, but had problems testing my water because of corona and quarantining. So I tested my water before weekly water change and parameters is:

Nitrate (NO3) - 20 mg/l
Nitrite (NO2) - 0
Ammonia (NH3) - 0
General Hardness (gH) - 12 dGH
pH - 7.5
Temp - 26 C (78.8 F)

As far as I understand parameters are normal and should not effect fish.

And they not getting picked, just males chase females from time to time. But both genders are getting sick, so it should not be because male tires females.

 

[Comanch]

Can it be parasites, because I saw few times that mollies flashed with they sides on gravel and wood?

 

[elizae]

Have you introduced any new fish recently?

Mollies like very hard water and a high pH. Any livebearer does really. Flashing indicates something is bothering the fish. Are there any white spots on the bodies or fins? Abnormal red? Or any other odd physical symptoms?

 

[Comanch]

Mollies was a first fish in my tank when it started 2 years ago and they lived without problems for most of the time, it just started few months ago. Last fish I introduced in tank was 15 glo danios ( few of them died, but I suspect it was from getting too close to spawning angelfish eggs). It was about half a year ago. Maybe they had something that started that mollies plague? But as far as I understand parasites and sickness is not that picky, they would not affect mollies only. And one more thing, mollies are getting lighter in colour then they get more effected and weaker. Hope that more info will help you guys to identify problems, because its sad to see those poor fish sick and could not help them.

 

[SaraB]

Sorry you have me stumped. Does it look like they are losing their slime coat lighter or just getting lighter in general? Do you have a lightly colored substrate? Because that could answer that.

 

[Comanch]

Not really sure how to different if slime coat is getting thinner or not. But I would say it more colour loss in general , like from jet black to dark greyish. My gravel is also mix from black to dark grey, but I don't think that because of it, because colour loss is noticable only on fish that have problems with swimming, and others is normal black colour.

 

[elizae]

Are the fish eating and losing weight?

I have noticed some mollie colors are weaker than others, probably due to breeding. Black mollies normally struggle the most, and the hardiest seem to be silver/white ones.

Change in color is stress. Do you know your kH? It determines how much your pH shifts. Does it happen after water changes, or does it just occur randomly?

 

[Comanch]

They are eating normally and even when they have difficulty to swim normally they try to get food.

I don't have kH test right now, but will get it in few days and will know number soon.

It occurs randomly, one day molly is ok active and swims normally and next day it starts to swim a bit at angle and day by day it loose more control of swimming and eventually dies.

 

[Comanch]

So I did kH test and its 11 dkH. Is it normal or too high?

 

[elizae]

You want a freshwater aquarium at about 4-8. Your kH and gH (maybe pH?) I believe go hand in hand so if one is high so should the other.

I was just now able to view your video and I have two concerns. You have some VERY swollen mollies. I cannot tell if they are balloon hybrids. It looks very much like a swim bladder/bloat issue. How much do you feed them? Even if they are pregnant females they shouldn’t have extended bellies like that, unless they are ballon mollies. I can see quite a few wobbling while they are swimming. Their spines do not look quite right either. Have you raised them or are all of them from the store?

I think you might be over feeding the aquarium. I saw some gold barbs and they looked very large too.

 

[Comanch]

I had cut feeding in half (now feed only one time a day instead of to) for about three weeks now, but it looks like it did't helped. Still new mollies are getting sick. And they getting pale when they have trouble with swimming:

It is a bit blurred photo, but the black in front is normal color and one in the back is sick and got almost grey in color. Only female looks swollen, males just loose color and have difficulty swimming.

Also one of my angelfish started to show similar symptoms. It have have difficulty staying afloat and lays on plats most of the time and just swims at feeding times and it looks like that he eats normaly, but he is very thin compared to other angelfish:

Video (it's in mid of water change so water looks not clear):
https://photos.app.goo.gl/X9zo6iynby3Bz9Pr8

And other thing I noticed today, one of golden barbs are missing few scales on his side. I don't know if it is related to my other problems or he just scratched in a rock:

Do you guys recommend to do something to help him grow it back or he will do it without my intervention?

So maybe more details from me will help you identifying problem and finding a solution for it, because it's hard to see poor fish and don't knowing how to help them.

 

[Fishlegend]

Looks like you need a good ole fashioned salt bath! Mollies are actually brackiSh water fish so you could try salt baths

 

[elizae]

The barb will regrow his scales, they just may not look the same as the surrounding or previous scales.

I know it’s hard watching fish suffer, it’s no fun. Now that it has spread to the angels we can start considering that something is in your water and it is not just the mollies. I’m assuming your water is still good? Have you added anything to the tank recently? Decorations, plants, fish, snails, medications, anything you can think of. Was something spilled or overdosed into the tank (like co2 or any other nutritional supplement)?

Yes mollies are technically brackish fish but they’ve typically been raised in generation after generation after generation in freshwater. If a fish has lived in freshwater it’s entire life and you suddenly put it in salt, you risk the same damage as you would a normal freshwater fish. Until we know what is affecting now two different species of fish in the tank, I would hold off on any salt. Salt baths are hard and stressful on the fish and if it’s done improperly can cause organ damage, so I would not do them until there’s at least some hypothesis as to why your fish are behaving this way.

 

[Comanch]

Few things come to mind:

• I started to feed frozen blood worms more frequently, before this started
• I used stainless steel mesh for making moss pads. But as far as I read stainless steel should not be messing up water.
• Fed fish flakes that was out of date without noticing it for about a month.
• Bought few new plants

Other than these things, nothing unusual or new happened in aquarium that could caused it.

Maybe something bad came with plants? Or I heard stories that frozen foods sometimes can be infected with something.

 

[elizae]

There are different qualities/types of stainless steel, and since it is not actually a pure metal, you can have different levels of iron, silicon, and everything else. I have not known for it to cause problems but if it does interact with the water, it would be adding more iron (I presume), which could be bad for the fish if its in incredibly high doses (which I doubt). If possible, can you inspect it for any change in appearance such as rust or anything else?

How are you storing/ feeding your bloodworms? If you thaw them you should not refreeze them. I've heard many stories from bloodworms and the general consensus I have seen is that most people don't like feeding them to their fish, and prefer other frozen foods, but that is just from what I've seen. Freezing them should theoretically kill any parasites or bacteria on them, but there is always an exception. People have had problems with fish gorging themselves on the worms, and experiencing deadly bloat. They have lots of protein, and produce lots of ammonia. I suspect that this might be what's causing it.

Were the plants kept in an aquarium with sick fish? That would be the only real way for anything to hitch a ride into your tank on plants.

 

[Comanch]

No visible rust or damage on that net. So it shouldn't be the problem.
Blood worms are bought frozen from shop which is few minutes from me so it still frozen goes to my freezer. I will stop feeding it for now, but personally I don't think it's the problem because I used it from beginning of aquarium (less often then now) and it was not a problem.

Plant was plated directly to aquarium so it could have something on it. What would you suggest I could use as a treatment? Yesterday I noticed that my rainbow shark is less active then usual and I fear it it got sick too.