I have male betta (crown tail) that I have had for a few months and he is normally very active and all up in everyone's business and happy and eats like a little piggy but 4 days ago he was very upset and lying on the bottom of the tank and not coming up to say hello or eat which is very out of character for him. His fins are also down which isn't normal.
His tank is heated with a thermometer, I have 2 live plants and a freshwater mussel for filtration in a 1 gallon tank.
I was sure something was wrong so I quickly did a 100% water change and scrubbed any algae off the side of his tank (there was a bit) and there was quite a bit of fishy poo (could it be an ammonia problem?) in there (more than I realised) and put him back in once it was all clean.
Thankfully he seems to have made quite an improvement and is eating now at least and comes to the top and he even made a bubble nest, but his fins look very sad still and I can tell he isn't feeling 100%.
I have before and after shots of his fins in the link below. Is there anything I can do to fix his fins and make him feel better? He is such a beautiful fish and I don't like the though of him not feeling well. Please help :(