Cntd from my question about fin rot- He’s now in a 5 gallon tank, without a heater atm, and no filter. Is it safe to add the filter from the tank he got sick in? I’ve added a bit of salt and some Bettafix. He’s made it through the night- I love this little guy dearly and am very upset this happened at all- i’ve had him over a year with no problems before. I’d appreciate any advice you have. Thank you for your time.
Thanks for asking. I invite anyone following me to pitch in if they have added insight, because disclaimer: Dean has never had fin rot, so I have not had to deal with it directly. Additional input is welcome!
That said, I did some reading, and it seems that fin rot is:
2. Caused by poor water quality and/or
3. Can be a consequence of some other thing that lowers their immune system and/or gives bacteria something to eat
You did good by putting him in a QT tank with a little aquarium salt. As soon as possible it would be good to add a heater too, because his body won’t have to work as hard to keep warm when it’s already working hard to fight the bacteria.
Bettafix is watered-down tea tree oil, which is an antiseptic. (Fatal in more concentrated amounts e.g. Melafix, but it’s watered down enough to be safe in Bettafix.) It will keep your fish clean since antiseptics are somewhat anti-bacterial, but if it’s a particularly bad case of fin rot or if it isn’t getting better in a few days then a specifically anti-bacterial med would be better, like tetracycline.
You’re going to be doing big water changes every day, so there’s no point in putting in the filter - the filter is where good bacteria are meant to live and it sucks up floating detritus. It holds a cycle in your current tank, presumably, but it won’t hold/make one in the QT tank.
Filter tip: take out the carbon packet in your filter. It filters out smell, but that smell can actually tell you a lot about your water. If it starts to smell a bit icky before your usual water change/cleaning, that’s a cue to check the water quality and/or do a partial change. Carbon also makes a lot of meds ineffective, and can kill good bacteria.