Molly fish dying

[Cyborg100]

Hi,

When I first got my fish I got some mollies. One of which had a huge stomach so I assumed she was pregnant. About a day later it was dead. I just assumed it didn't like it's new environment and therefore died. Now, however, another one of my molly fish just died with a huge stomach. Are they just dying from pregnancy or do they have a disease?

 

[fluttermoth]

Hi there, sorry to hear of your losses

How big is the tank, how long has it been set up and did you cycle it before you added fish? Exactly what fish do you have? Have you got water testing kit?

 

[Cyborg100]

Hi there, sorry to hear of your losses

How big is the tank, how long has it been set up and did you cycle it before you added fish? Exactly what fish do you have? Have you got water testing kit?

I have a 20 gallon tank that has been set up for about 2 weeks. I completely forgot to cycle it when I got my fish, so I bought a bacteria pouch to add in with the fish. I currently have 11 fish(12 including the once alive fish). I have a water test kit, but I haven't used it yet. I have 4 mollies(including the now dead one), 6 platys, and 2 fish that I forgot the name of.

 

[fluttermoth]

If you didn't cycle the tank, you need to be testing the water every day; you're now doing a fish in cycle, so you'll be needing to do a lot of water changes to keep the levels of ammonia and nitrite as near to zero as possible.

With that many fish in an uncycled tank, ammonia poisoning is the most likely cause of the deaths.

P. S. I should have said that looking at water quality is always, always the first thing you should do in any cases of death or 'disease'. Nearly all fish deaths and sickness turn out to be down to poor water (not all, of course, but nine times out of ten, that's where the problem is).

 

[Cyborg100]

Ok, thanks