Betta fin rot

So a while back my perants thrusted a beta on me without the proper means to take care of it. I did my best and things went really well for a while till he got fin rot, it took me a while to get meds because im a minor with no income so i did salt till then which slowed it, after I medicated him he got a lot better so i recently housed him with my other fish thinking he was better and fully recovering, however he has taken a turn for the worse and his fin rot is pretty bad now.
It got so much worse so suddenly and now his fins are going pink. I was thinking to put him back in his 1 gal and use both salts and meds till he is fully recovered but i wanted to consult experts before i do anything, he is still eating well and has some weight on him so i dont think he is a lost cause, im currently unable to provide heat via conventional means wich i believe is a huge factor, ive been using a heat mat and thats been helping and until now i havnt had a thermometer to check if its good or not. Thanks in advance and sorry for the wall of text.

Hello? Can anyone help? What can I do?

Ive no experience with bettas sorry but i will say that the bacteria responsible for fin rot will take hold when your betta's immune system is compromised by poor water conditions or as youve alluded to, low temp. You'll be asked about water parameters by members here so be good to post those, ammonia, nitrite, nitrate..

Thanks, because the tank is new that will be weird.

Wizard Lizard said:

Thanks, because the tank is new that will be weird.

Click to expand...

Not sure what you mean sorry? How new? Has it been cycled?

A couple days old

Does it have a filter?

Yes, it has an air pump under filter

For the 1 gal quarantine I have a back hanging filter.

If you tank is a couple of days old it is not cycled. (nitrogen cycle) You will have to do daily water changes. Your tank takes time to produce the correct bacteria to deal with the ammonia in the water from your fish waste and any uneaten food. Ammonia is very bad for fish and will kill them in a short time. I would suggest you picking up a bottle of Tetra Safe Start Plus. It has the needed bacteria to jump start your tanks cycle. This will help improve the water conditions and your fish's health. You should also pick up a water test kit so you can test for ammonia, nitrate and nitrates in the water.

I reused decor from the other tanks to help, idk if ill be able to get the bacteria, but i can do water changes, though ive never heard of doing daily water changes when starting a new tank

Ok cool. Just from what you had talked though initially it sounded like you'd had the tank(s) setup a little while. If thats not the case then yeh, as @Retired Viking has explained, your filter(s) need chance to grow the beneficial bacteria that turns the toxic ammonia (fish waste) into less toxic stuff (nitrate). The most important thing you should trycand do now is water changes to remove most of the ammonia in order to save your fish, then concentrate on the salt/meds. Check out the pinned posts in this forum for 'fish-in-cycle'

I reused the filter media as well so that is already up and running

The reason I spoke about daily water changes is because as I understood it , you have the betta in a one gallon container. The smaller the amount of water the greater the harm the ammonia the fish produces will do. In a larger container like a 10 gallon tank you have much more water to dilute the ammonia produced by the fish so it takes longer to reach a dangerous level so water changes can be less often. I hope that makes sense.

Do you have a water test kit that test for ammonia? That is good that you used the filter media, that may take care of the ammonia. A test kit will make sure there is enough of the good Bacteria. Sorry for the question just trying to make sure I understand your situation clearly.