NUOLUX Fish Breeder Hatchery Self-floating Fish Breeding Box (Transparent) This is Aquarium Nursery Fish Tank Self-floating Fish Breeding Isolation Box Breeder Hatchery Incubator. Color: Transparent. Material: Acrylic. Size: Approx. 12.6 * 7 * 7cm. Can be used as the spawning box for the viviparous fishes. Prevents adult fish attack so as to improve the survival rate of juvenile fish. Can separate aggressive fish, injured fish, small fish, shrimp, and other sea clownfish. Unique transparent cover design, preventing fish jumping out of the box.