Thank you @Ch4rlie, I went into total panic when I realised he wasn’t ok and really don’t feel confident In myself yet even though I have read countless information on here. The reassurance really means a lot, thanks again.Sounds like you are doing all the correct things that would have been advised for your betta.
Keep up the good work and hopefully the fin should heal and repair itself with good quaility water which is what you are doing by doing these water changes.
I use Indian almond leaves already and I have heard bad things about melafix. Is it definitely fin rot because he had a major injury after jumping into a soap dish that was being used to baffle the flow from the filter and it’s just got worse but none of his fins have broken or come away or anything?!?