...and we have a huma with a porcupine and a panther, no problems at all. Huma was added last. As a matter of fact, the panther (who is HUGE) eats formula one frozen, and I dropped it in the tank the other day...he accidentally grabbed hold of the huma as he was going for the food, swam across the tank with the trigger flat against his mouth, then let him go. The huma had no ill effects, and the panther went on to eat his formula one.