Yeah, as long as he doesn't have bladder sludge issues, you can gradually introduce alfalfa hay into his diet. The added protein should help him keep his weight up. Plus you won't be getting the added carbs from feeding extra pellets. You do want to slowly introduce it, like you do with veggies or any new food. Start with a very small amount each day for a few days, keeping an eye out for poop changes, then gradually increase if the poops stay ok. You'll want to wait a few days til this last stasis bout is settled, and he is having normal poops and behavior for several days. You want a good green alfalfa with small stems and lots of leaves. The smaller the stems and earlier the cut, the higher the protein.
Now that he is eating hay, you may want to cut back on the pellets, in case that was the cause of the stasis. Also don't feed any other sugars and carbs. Him eating lots of grass hay is going to keep his digestion moving better and get the gut balance restored. Unless there is a parasitic problem, like the cocci. But if his poops have gone back to normal, and there isn't any more mucous, then it's most likely that cocci wasn't the problem. With him eating unlimited pellets, that could very well have been the cause. If his poops have gone back to normal and he is acting normal again, on a reduced pellet diet, then he may be fine, but if you are concerned about other illnesses causing this, then it probably is best to get the tests done, to rule those other things out.
