Swimbladder problems?

[Finney]

Hi all,

I have recently lost 4 tetras to what seems to be swimbladder related, I haven't had this issue before.

First 2 fish were red eye tetras, all fish and tank have been fine/no illnesses for a year or more (in this tank). I suddenly found red eye tetra #1 nose down in the weeds, breathing fine, color normal, would try to move/swim but only able to wiggle to another spot without swimming. I seprated him into a specimen container in the tank and put ResQ in his water, he would move around, but did not eat and after several days he died. 

A few days later Red eye tetra #2 did the same, no warning signs and the only thing wrong was not being able to swim though he was strong enough to move himself around the tank to different spots. I left him in the tank and other than using ResQ I didn't medicate at all as I had no idea what would help.

I then lost 2 Lambchop Rasboras, #1 seemed to be wasting away over a week or more then disappeared so I never saw him have trouble swimming, #2 had part of his tail missing and I assumed injury but didn't see it happen-there has never been any aggression issues in this tank, he seemed okay and I hoped he would recover from the injury then suddenly he was dead but floating at the top.

I now have a Cherry Barb that is struggling to swim but manages to swim in the water colum irradically before laying somewhere in the weeds on the bottom to rest. Color is normal He still tries to eat but wears himself out, he is probably 6+ years old.

I am not sure if or how these situations are related but since everyone had been fine until the last couple weeks I assume they are somehow.
45 gal
75 degrees
Ammonia 0
Nitite 0
NitrAte 20
KH between 40-80 on test strip
GH 300 (tap water is 150 and I have some wondershell in tank)
Planted
part of a wondershell
Filstar XP2 canister filter-which was overdue for a cleaning & I just cleaned it but water params have been fine-NitrAtes highest at 40 before cleaning it.
spray bar & airstones to keep oxygen up as I have Hillstream loaches in this tank

Current inhabitants:

1 Red eye tetra
7 Lemon tetras
5 Cardinal tetras
2 Serpae tetras
2 Otos
1 Kuhli loach
3 Hillstream loaches
1 SAE
1 Cherry Barb-current swimming issues
2-4 Amano shrimp-they are hard to find in the plants

I have not added any fish since since January

Again the 2 red eyes and the cherry barb did not look sick but the lambchops, 1 was pretty thin and not eating much then disappeared, the other was eating fine and swimming fine but looked injured but seemed like he could recover, then just died-he floated though.

Any idea what might be going on?
Other than water changes, ResQ and cleaning the filter I haven't tried any medications

Thanks in advance for your advice

[devonjohnsgard]

Any bullying going on in the tank? The stress can kill off fish slowly. Everything else looks fine.

[Finney]

No bullying that I've ever seen, only one of the lambchop tetras had any kind of injury and that one was swimming fine and found floating when he died.
The first 2 Red eye tetras died on the bottom of the tank and could not swim befor dying, with no injuries and good color, no leading sickness before being found on the bottom of the tank.

Is there any bacterial infection that would cause these symptoms even when everything else seems fine?
Could a dirty canister filter introduce something to the water column that doesn't show up on the test strip? All tests have been fine which is partly why I let the canister go for a while...

[Carl]

Nov 19, 2020 13:26:38 GMT -5 Finney said:

No bullying that I've ever seen, only one of the lambchop tetras had any kind of injury and that one was swimming fine and found floating when he died.
The first 2 Red eye tetras died on the bottom of the tank and could not swim befor dying, with no injuries and good color, no leading sickness before being found on the bottom of the tank.

Is there any bacterial infection that would cause these symptoms even when everything else seems fine?
Could a dirty canister filter introduce something to the water column that doesn't show up on the test strip? All tests have been fine which is partly why I let the canister go for a while...

Sometimes an intestinal infection of Aeromonas can cause cause floating symptoms but nothing else.
Aeromonas can breed in poor substrate or stagnant filter conditions, but I have my doubts that this happened based your information.

Honestly this is a tough call.
Any changes in feeding and what have you been feeding?
Do you use a True UV Sterilizer?

I would consider some fish baths with salts, MethyBlue, and AAP Naladin

I would also consider treating the main tank with AAP Naladin

Resources:
www.americanaquariumproducts.com/Aquatronics.html#naladixic
www.aquarium-pond-answers.com/2009/07/fish-baths.html

[Finney]

Thanks Carl,

Currently, all sick fish have died so I am just watching the rest for any signs of trouble, they all look healthy right now. I study my fish 2-3 times a day and more if there are problems, the ones that have died just seem to go from all good to laying on the bottom; I work from home so I tend to "stalk" them a bit .

I do think my water condition is good, I have a fairly high flow rate in this tank due to the Hillstream Loaches.

I have been feeding the same food for a long time
-Zoo Med Spirulina 20 flakes
-Omega One Seafood formula flakes
-Hakari sinking wafers for the loaches 1-2 x a week, the tetras don't eat these
I alternate these and feed once a day, with Rapashy Soilent Green 1-2 x a week and (frozen brine shrimp but I have been out of that for a while)

I don't have a UV Sterilizer-money is to tight for that right now.

I will continue to watch them closely and if another one gets sick I will treat the whole tank with Naladin, I have some on hand.

Thank you both for your help!