Get him out of the tank and into a cage. If he's weak, make sure he doesn't have levels or a wheel. Tanks provide no ventilation and he will be prone to overheat. Unless you clean up after him, there will also be an ammonia build up which will not be good for him.I fed Gus 5cc and he's now in isolation in an old fish tank with screened lid, covered on the sides to keep it dark....I've been told to feed 3-6cc every 4-6hours and if no improvement in 24 hours - back to the vet.