I have a beautifull 75 gal tank with 5 med ryukins in it. All my water quality is good,  I make frequent water changes and the temp is 72. My problem is one on the smaller ones gets constipated whenever it eats. Here is what I am feeding now.. a.m. soaked flakes either reg or veggie, p.m. sinking pellets. Once a week just shelled peas, also bloodworms as a treat on the weekends. I try to keep their diet as varied as I can. When the little one get's to the point he is floating upside down, I do a 24-48 hour fast. Afterwords he is fine untill he eats again, and it strats all over again. I do not have a hospital tank to put him into,, I have no room!! Any suggestions??? Thanks  Karen