This has been happening to his clowns- he recieved some new ones, and they were getting along perfectly fine. Plump, brightly colored, active, playful, eating fine. Then one day one of them starts breathing really rapidly and flying around the tank like it'd gone crazy. Minutes later, it's dead.


I've been scared about this ever since. The pet store owner suggested it was an internal parasite, and a difficult one to pinpoint before things start getting deadly.
This has now happened to three of my friends loaches in a matter of about 2-3 days. He's got maracyn II but they all died so soon. He's got two clowns left and has no idea if they're affected, and who else in the tank may be. They seemed to have died so abruptly and very disturbingly. One of the clowns from the pet store died of this as well, and the clown tank is now being treated.
Has anyone seen this, and can anyone give me information on these horrible internal monsters? I'm still very uncomfortable by what I saw.
I'd love to get as much info as possible, in hopes to save the remaining clowns.