Help with sick betta, possible gill hyperplasia

[Dstewart27]

Hey everyone, our betta fish that we have had since June started being lethargic about a month and a half ago and started laying on the bottom of the tank seemingly out of nowhere. We moved him to a hospital tank and raised his temp from 79 in his original 10g home up to 81/82 degrees and did treatment rounds of kanaplex, salt and prazipro. He breathes very heavily but still eats regularly and looks normal when he swims to the surface for air and it’s not uncommon for us to see him swim for about 5-10 seconds before he lays back down for a long while. We think he’s having a gil problem, hyperplasia is our best guess based on breathing problems and how his gills look inflamed. Over his last month of treatment his condition hasn’t worsened or improved, we were wondering if anyone had suggestions such as upping the number of treatments of some type or if it’s not likely he will recover if we should put him down. Thanks ahead of time. 
 

ph-7

ammonia 0

nitrite 0

nitrate ~10

gh/kh unknown but the tap water is on the harder side but his tank had a good amount of wood and almond leaves leeching tannins 

temp 79 in main tank, 81/82 in the hospital tank 

[Colu]

Gill hyperplasia can because by increase number of cells caused by a  tumor Gill injury or a bacterial infection.what I would do is add Indian almond leaves 1 leaf per 1 gallon as they have antibacterial and antifungal properties and Aquarium salt 1 table spoon for 2 gallons if you have live plants salt at that level will harm or you can do a course of kanaplex in food and the Indian almond leaves