Ok, so we got two figure 8 puffers on Tuesday (5/5/09). One larger than the other. The larger one is doing great, healthy swimming and eating. The smaller of the two has been acting weird since it was put in the tank. When we released it into the tank he quickly spiraled down to the bottom of the tank and laid on the bottom. He laid there for a while, as if he was trying to gain energy and got up and swam for a bit. But his 'swimming' consists of the current moving him aorund yet all of his fins are going. He can direct himself, however he runs into everything, plants, filter, glass, wood, rocks on bottom and doesn't eat. His belly is sunken in. The large puffer is eating frozen mysis (spelling?)and brine shrimp along with live snails. We brought the water to the pet store and he said everything is great. Any ideas?