Hey, so I think I know what this is but I'd rather be safe than sorry.
Recently my red betta male had gotten sick (there was something in his tank that had apparently poisoned the water, it was removed and I transfered him to another tank to recover) He was acting very lethargic, so I checked his water, that didn't seem to be the problem. Then he just started laying behind his filter on the bottom of the tank, I'd have to get his attention so he could go up for air (he was under constant surveilance) or he'd just lay there unmoving, his red grew pale and he stopped fanning out his fins. It didn't take me long to realise he was sick.
I started feeding him the occasional skinned/thawed pea which he happily ate, he's acting normal now, at least somewhat. He's swimming around and poking at random things like he used to, but now there's this mound hanging from I string. I'm pretty sure he just passed a good amount of waste from the pea(I thought it could have been SWD) but I just want to make sure that he really is doing much better and I have nothing to worry about.
This is a photo I just took this morning.
This is just waste, right?
Thanks, guys. I'm kind of a new owner(Haven't owned one for a good 10 years) and I just want to make sure my Bettas are happy and healthy.