Likely a dumb newbie mistake ahead: I think I know the answer to my question but figured I'd ask it here anyway....I bought 6 oto cats and 12 furcata rainbowfish and have them in a 5 gallon quarantine tank. I put a heater in there but it sent the water up to 82 degrees, so last night I unplugged it. This morning found 2 dead otos and another dead rainbowfish. Water was 74 degrees. Is the temp swing likely what killed them? I just got them 2 days ago but they looked healthy at the pet store and all the rainbows are eating well. A third oto just died mid day. Really mad at myself but am hoping this is my own doing rather than a problem with the crop of fish I bought.