I  know this is somewhat gross but I'm trying to figure out if my fish has some issues and if I'll have to take him to a fish psychologist. My male fantail likes to get right up to the butt of my other fish and eat their poop. Sometimes he spits it out but most times he eats it. He is a huge pig and will race to eat the food and even when he has a mouthful, he still tries to eat all the food. Is this normal snacktime behavior?

Mine dont  chase poop anymore. Umm.. I'm pretty sure its normal. I mean, plenty of animals do eat their poop; it could be a psychological thing, I'm not sure though. In any case, you should probably check with a vet or an aquatic life specialist to see if this is healthy for your fish

Sure he doesn't spit it out?
Our fishies sometimes think poo is sth edible ( same colour as their food sometimes ) but they spit it out with a disgusted expression on their faces.

Yeah, fish don't see real well so anything that moves in the water is food to them.
I say pretty normal behavior and watch for a growth spurt soon if your fish is always hungry like that!

On occasion he'll spit it out, but lately he's been munching on it. I know it's gross, my dog used to frequent the litter box. YUCK. I think I'm feeding them well. for breakfast they've been getting a mix of Omega One Goldfish Pellets and hakkai (purple bag) and I change up dinner daily between gel food made from babyfood (garden veggies with sardines) along with peas, carrots and zucchini and then I feed them sometimes the Omega One Veggie flakes.  I guess I won't worry about it, unless he keeps it up. It's funny because last night Teetsy was hiding behind a rock structure going potty. I guess she's tired of him poking around her business. 

If he continues this behavior and doesn't seem to be growing much, I would maybe feed him an anti parasitic food...he may have internal parasites!