I have 2 zebra danios. Use to have a school of 6 but i’ve had them for over 4 years so some have unfortunately died. I’m not going to buy more because I simply cannot have a commitment of 5 more years. So the 2 that i currently have remained in their 20 gallon for a while until i needed it for another fish. I put the danios in a cycled 5 gallon. I assumed this would be ok because typically 6-8 danios are kept in a 20 gallon so that’s about 2.5-3 gals each. I just want to make sure that this is ok. They have always fin nipped eachother but i’m afraid that it might be getting worse. I’m moving soon so could try and get a 10 gallon but their again like 4 years old. Let me know if you think I should, i do care about them a lot. Water changes 1-2 times a month. (i’m away at college so my mom is taking care of them) Ammonia and nitrite always 0 but not sure of nitrate.