One of my six rummies is not eating, and getting very skinny. Before I pull it out of the main tank into a hospital tank (or cull ), I'm wondering about cause, and prognosis. Tank is 20gal, planted, and well stocked. Water parameters are good: Ammo & nitrites = 0, nitrates are <10. pH is 7.5. Not sure about exact hardness, but it's high. Tank mates include pygmy cories, neon tetras, otos, and honey gourami, all healthy. The skinny rummy is interested in food, but not eating. I've tried basic flakes, sinking micros, and minced bloodworms (fun job, right?). It actively pursues food when added, bites it, but spits it back out. I acknowledge that stocking is high, and will be upsizing to a 30 when I can. But I'm diligent on WC's, parameters are good, and all other fish are healthy. I have treated with Prazipro recently, so it's not likely to be any of the internals that it would treat. And I see no other symptoms of illness (mostly schools with other rummies, no flashing or gasping, no marks or spots, etc.). I can't confirm fish's age, but it's been in my tank for about 6-8 weeks (purch from LFS). It's my first time with rummies, so I can't say for sure how grown it is, but if it's not full sized, it's awfully close. I know it would be easiest to cull it, but don't want to go down that road if it's unnecessary. I'm thinking its just something going on with this fish (ie no risk in leaving it in tank and crossing fingers), but if any of you out there see a different pattern here, and recommend culling or hospital tank, please share. I've fed lightly cooked shelled peas before, but have never seen any interest and always end up netting them out a day later. FWIW, I don't have a hospital tank running, but could set one up pretty fast. Thanks for any help.