I've been growing out a group of HRPs that I got from Rapps - growth has been very slow. The fish are very skittish and I've noticed swollen bellies on a couple. Yesterday I saw a long whitish poop coming from my largest fish(first time I've noticed this). I've been feeding live blackworms as a treat and maybe my fish picked up something? I'd like to do a worming treatment. What does everyone recommend?