Hi all, I’ve just recently gotten into betta keeping, I have 3 at the moment, all are in cycled 5.5 gallon tanks. My blue vieltale (1st purchase) has developed strange brown spots/patches on his gill plates, possibly (hard to tell) on lower part of beard and just behind his ventral fins. The rest of his body looks fine, doesn’t look like velvet as it is not rust colored and only appears on areas mentioned above. Any ideas on what this could be? I do twice weekly pwc’s treated with prime, gravel vac twice weekly (snail is messy), current water parameters are 0 ppm ammonia, 0 ppm nitrites and between 10 & 20 ppm nitrites. Water is at 80 degrees. Not rubbing on any tank decorations, eating fine, acting normal, (maybe a bit more active than usual when i approch his tank lately since he has to share my attention with two other tanks, so i can’t stare lovingly into his eyes as much as he was accustomed to). Dumb question, but I am dealing with diatoms in all 3 tanks at the moment, could they be attaching to him? Any replies would be much appreciated.