mollys dying need some assistance

[jgonzo07]

I am new to AC and was hoping someone could help me uncover what I might be doing wrong with newly introduced mollys. I prepped an 8 gal (US) tank for 8 weeks, had a platy and that's all until this weekend. I purchased 6 neon tetras and 4 mollys. All save 1 of the mollys have died within 24 hours. PH is 7.4, temp is 80 F and no Ammonia is present. I even went to the shop I bought them and received 2 more mollys and those also passed. They tested my water and confirmed above. I haven't checked hardness, could this be the issue?? Please help as my son and daughter and I are very scared to go to the aquarium in fear of finding more casualties. What have I done? :help:

[shalafi04]

what are your nitrite readings? When you say your prepped the 8g. what do you mean? Dechlorinate? is it cycled?

[jgonzo07]

I cycled the tank for several weeks before adding the new fish; all I had was a pleco before adding the newbies. I dechlorinate my tap water, and let sit for weeks before use. PH is stable. Nitrite test is something I haven't checked, but why just the mollys and not the Tetras? Could it be a disease from the shop I bought them from?

[fishfanatic33]

Hi and welcome to AC. You need to check the Nitrite and Nitrate. And what do you mean by "Let it sit for weeks"? You have to be running the filter

[jgonzo07]

Okay I'll run a nitrate/nitrite test. As for the cycling of the tank prior, yes the filters were running, the water seemed stable (outside of the nitrite which I didn't test for!!). Still, the tetras and pleco are doing great, are the mollys more sensitive?

[jbeining75]

Might just be a bad batch of mollies.. Are you drip acclimating them to your tank or just dumping them in....

[country_boy454]

Welcome to the forum!

[cocoa_pleco]

welcome to ac!

the mollies will need a 33g, but otherwise i think for the time being you got a bad batch of mollies

[shalafi04]

yeah i still need a definition on "let it sit." because it has to have a constant supply of ammonia in order to cycle otherwise you are gonna be cycling with your fish in it and well... ammonia and nitrites kill fish

[AquaBANG]

I think you introduced too many fish in a shot (6neons and 4 mollies) for a 8G tank, may be it was cycled, but too many fish can lead to ammonia and nitride build up which can kill fish. Neons are very sensitive fish. Mollies are hardier but I think it was bad luck.

[shalafi04]

I think you introduced too many fish in a shot (6neons and 4 mollies) for a 8G tank, may be it was cycled, but too many fish can lead to ammonia and nitride build up which can kill fish. Neons are very sensitive fish. Mollies are hardier but I think it was bad luck.

good point. if the batch of mollies was weak to begin with maybe the ammonia or nitrite spike was small but ended up having a big effect on them due to them not being up to par.

hope your issue resolves itself. id wait a couple weeks before putting anyone else in the tank and continue testing the waters to ensure that its stable

[Asphenaz]

Welcome to the boards, hope you find out what went wrong.

[J1400Smith]

I think you did not have enough bio load to support that many fish introduced at one time. Not to mention the overcrowding of the 8 gal tank. How did you cycle the tank to begin with? If you don't cycle properly, you need to add fish slowly to build up the bio load. If you did not cycle properly before you added the fish, then yes you will lose fish until it is cycled.

[aquarius56]

Hello and Welcome :22: