Hi guys - Ok he's starting to attack his pellets with energy and can swim with a bit more freedom of motion now.
I used a bit of API salt also this morning after I 100% cleaned his 2G hospital tank once the white fuzz fell off. I cleaned the tank, heater and betta log in scalding hot water for a minute also.That's all that is in it.
When I get home, I will dismantle/deep clean the 10G split & also keep using the antifungus stuff & salt for the duration of 7 days as the bottle says. That way his tankmate Blackbeard can be treated IF he was exposed to whatever this was.
I think Numbus being white made it less obvious to me....I can't imagine this fuzz sprouting up so quick!