I recently got two new Green Spotted Puffers from a Walmart where they had them with guppies.... dont even get me started on that idiocy. But I took them home and I have had them for a week. They looked like they had fin rot and a fungus but when I acclimated them to the brackish water ( SG being 1.008). They were being fed on snails for the first three days. One of them the smaller one took to them and has fattened up quite nicely. But for some reason the larger one would chase them suck them up but wouldnt eat them. I switched them over to Daphnia which the fist took still and the second also started to eat. But the second one seems very thin and not as round as he should be and about an hour after I feed him he goes right back to being super thin. He still looks super thin even when his belly is full. Right now they are being housed together but will soon be separated (as I only had one cycled brackish tank available).The first three are some pictures of him i cant get a good one of his belly because he is still as super active. And the fourth picture is of the first healthy seeming one.