Internal parasites in bettas

Hi everyone! :hi: I hope I didn't post this in the wrong forum.

I've noticed that my little betta appears to have internal parasites. When he had a bowel movement today the feces was white and stringy. I started him on Jungle's Pepso Food but I don't know how much to give to him. The bits are very small(smaller then a pellet) so I only gave him four pieces. Should I be giving him more and how well does this stuff clear out internal parasites? The reason I ask this is because he has SBD and the symptoms have been on and off so I know there's no permanent damage and I have a feeling that the parasites could be what's causing this.

Oh and right now I have him in a 1/2 gallon tank but I have a 2.5 gallon tank that's ready for him to go into. Should I wait to finish the food for three days(like it states on the bottle) then put him into his larger tank or would it be okay to put him into his new home now?

Thank you.

Hi MightyQueen,

I'd say at the most, he's a year old but I don't think he's reached the one year mark yet. The only pictures I have of him is before he was sick. He has lost a bit of weight but he's still eating good and he's active but not as much as before. The reason I think it's internal parasites is because sometimes he will twitch for no reason. I shined a flashlight on him to see if I could see any parasites on his body and I didn't find any.