Dead fish- please help me

[Passionateaboutcetaceans]

Hello! I’m new here and could really use some help and advice. I set up a 55 gallon tank. I let it cycle etc and then added my female bettas. I have a sorority going in the tank. I had 25 female bettas along with 4 albino Cory catfish, 2 tiny baby angel fish and 2 large plecos. My husband bought some neon tetras the other day and also moved over his 2 gold mollies in the 55 gallon tank. He moved the mollies over on Saturday night. Today is Monday so about 48 hours. I came home last night and noticed a lot of my betta girls had nipped tails and one of my bettas was breathing very hard and on the bottom. I quarantined her and she passed away in the middle of the night last night. Today I came home from work and found 2 bettas dead and half eaten. In total, I lost 4 bettas and both baby angel fish. I believe it’s the mollies that my husband put in. Please help me. What did this? I’ve moved the mollies out. Water parameters were checked and everything is ok.

 

[Colin_T]

Hi and welcome to the forum

Can you tell us what the actual water test results were?

The best thing to do if you ever lose a fish, or a fish looks unwell, is to do a 75% water change and complete gravel clean each day until the issue is identified.

If you can post a picture of the fish that also helps.