I have a betta purchased from petsmart 3 yrs and 1 month ago. I have watched a white growth slowly spread on his tail area for several weeks. I have recently transferred him from his previous 1.8 gallon tank to a 10 gal aquarium to hopefully keep a better regulated temperature, which was difficult in his smaller tank.
The fish has his normal behavior: curious, good eater, etc. I have treated with fungus clear per directions twice to no apparent success. I am two days in to a 5 day regimen of lifeguard tablets. Im just not confident he has a fungus and/or tail rot. Could this be somekind of growth or other diesease?
His tail area is reduced, IE the space between the rear tail and belly tail is wider apart, and the white 'thing' is irregular edged, vividly white and curled up, reminscent of spray insulation foam, but not fuzzy in my estimation. Also on his other side you can't really tell anything is happening to his tail!