Dying Fish

[LionessN3cubs]

My water stats are ammonia 0, nitrite 0, and the nitrates have to be low because I just did a TOTAL cleaning on the tank about a week ago.

I lost my 1 mollie, which I'd thought he'd gotten stuck trying to get to the platy fry. That was about oh I dunno...2 months ago?

1 month ago I lost my blue platy....she wasted away to nothing and died.

Now I lost my other mollie...she was fine yesterday. Swimming around and eating fine. Hadn't looked sick either.

I still have 2 adult platies and 4 platy babies none of which look sick at all. if there was a sickness in the tank wouldnt the smallest of the fish be suffering too?

If it means anything, the only fish I've lost are the originals I bought from the fish store about 3 months ago? roughly? I've had TONS of fry so far roughly 10ish and NONE of them have died except those that were eaten or otherwise removed. I also have an apple snail that is fine in the tank.

Any ideas what is killing my fish? Like I said, I totally ripped the tank apart and cleaned everything in hot water (NOTHING else, just water) ...my bacteria are fine because I have NO ammonia and NO nitrite and being slightly overstocked as I am I would notice a spike now if that were the problem. I also remembered to add the dechlorinator (using pond dechlorinator like miss wiggles suggested in case it matters) so it wasn't that. I dont know what the water temp is because the stick on thermometer strip I have is totally wrong...it says 86 but I KNOW that isn't right..my heater is set at 79 and it kicks on every now and then so what Im saying there is, I can feel that the water is about right temp AND the heater is agrees with what I feel...its not too hot in there. I also have plenty of oxygenation going on.


I just dont get it...that fish was FINE yesterday and now today she is gone

 

[Colin_T]

If you washed the filter out with hot water then you would have killed the beneficial filter bacteria and you could get an ammonia reading soon. If you didn't wash the filter media out then chances are any diseases are still alive and well in the filter material.
If the adult fish were dieing they could have had intestinal worms, gills flukes or some other disease. Many internal diseases only cause problems to the infected fish. If the babies were not infected they would be fine while the adults die.
But without a pic or better description of the dead fish it is hard to say.

 

[LauraFrog]

What happens is that fish that are at the LFS get infested with parasites. LFS tanks are almost invariably small and overcrowded. Some fish die. Due to the conditions in which they were mass produced for the trade most have parasites. the other fish eat the body and get the parasites. This is virtually impossible to avoid. Fish TB can also be infected this way.

If your problem is fish TB it is incurable, but what I'd do if I got another fish wasting away was treat with antibiotics, then after that treatment use an anti parasite medication. If that fails it's probably TB.

Did the molly that died show any symptoms before you lost her or did you just find her dead for no reason?

 

[LionessN3cubs]

What happens is that fish that are at the LFS get infested with parasites. LFS tanks are almost invariably small and overcrowded. Some fish die. Due to the conditions in which they were mass produced for the trade most have parasites. the other fish eat the body and get the parasites. This is virtually impossible to avoid. Fish TB can also be infected this way.

If your problem is fish TB it is incurable, but what I'd do if I got another fish wasting away was treat with antibiotics, then after that treatment use an anti parasite medication. If that fails it's probably TB.

Did the molly that died show any symptoms before you lost her or did you just find her dead for no reason?

I found her dead for no reason. She was fine on sunday...swimming around and looked healthy. The blue platy that died literally wasted away ...got skinny and sick looking...the mollies didnt look sick at all.

 

[rabbut]

Well, two things could be going on here... Just remind me, did you fish-in or fishless cycle this tank? If it was fish-in cycled, this could be that the ammonia poisoning has come back to bite you. Fishless cycling, assuming it was successful though will rule this out.

Secondly, all your deaths are livebearers from that list aren't they? Sometimes I find some tanks simply can't support livebearers with no logical explanation. At work there are two identical tanks next to each other, runing with water stats that are as near to each other as makes no difference, that run the same equipment at the same temperature with the same maintanance carried out on them using the same water source. One tank supports all fish well, the other gives greaf with mollies platties and guppies, but nothing else. It's weired, to say the least. I also know of a customer's tank that runs the same way... Do you have any other fish in there? If so, are they faring OK? If so, I'd assume your tank is amongst a rare few that cannot support livebeares for whatever reason, and avoid them in future stocking plans.

Just my thoughts...

With no bodys or symptoms to look at though, I would not yet consider disease, unless you start loosing them at a rather quick rate (like a few in a week) TB isn't tank common, and bacterial infections would be moving quicker. If disease is at play, I'd bet on an internal parasite personally.

HTH
Rabbut

 

[waterdrop]

hi rabbut,

I believe she did a good job fishless cycling and knows those principles quite well.

~~waterdrop~~