Rescued Betta With Fin Rot

[Josie*paolillo]

Basically, I have taken this betta off my sister as I saw him for the first time in weeks and he has ended up with finrot. He was in a 3 gallon ( filtered and heated) but I got him into an 8 gallon I had just finished cycling for endlers (sigh) so his fin rot looks pretty bad, and I'm wondering if daily water changes and a good diet is going to be enough. His health over all is pretty bad, he had been being fed broad spectrum flakes, and his colour wasn't so bright. He is now on new life spectrum pellets, blood worms and brine shrimp.

I have aquarium salt, just don't want to use it unless its a last resort. I have four tanks (100G, 20G, 5G, 8G) but I have never had to treat fin rot. His dorsal fin looks like my crowntails, the rest is ripped and blackened and ragged. Here's a couple of pics, let me know what you think

 

[Wildbetta]

While his fins do look pretty rough, I believe with very clean warm water and a good diet you should start seeing improvement pretty quickly.  I would keep his water at 82F to help promote healing.  

 

[Josie*paolillo]

I've turned the heat down to 79 to prevent the Bacteria growing more. Im hoping that too, already there's a tiny bit of new growth on the less affected areas, I'm just worried about the huge splits in his fins

 

[Wildbetta]

Bettas really like warmer water and it helps their immune system so I would being the temp back up to 82F instead.  The bacteria really should be no match for him with warm clean water and good food which will enable his immune system to do its job and help him fight off any issues as well as help the fins regrow.  The fin edges will appear clear when they are growing back in and will eventually get color back to them.