12-15cm.
The Topaz Puffer is a tan to green with many, large, black spots covering the back and sides. The belly area is an off-white and lacks any markings.
The ideal aquarium will have brackish water with many plants (either real or plastic), rocks with plenty of hiding places, and a sandy bottom composed of an aragonite-based sand. The Topaz Puffer can be aggressive to members of its own species, so care should be taken when housed together.