Actually Blacktip reefs can get to be at least 5' and possible 6' long. So the pond is definitely too small for a blacktip reef shark. Also it's too small for a Spotted Wobbie - since they will reach 8-10 ft long. The Epaulette on the other hand is a perfect choice for that pond. Since it will only get to be about 36-42 inches long when full grown, and they live in tidal pools in the wild - where space is often as tight or even tighter than that pond is.