How Often Do Glow Fish Lay Eggs?

GloFish are genetically engineered zebra danios, the first genetically enginnered fish to debut in the aquarium trade. These fish have a gene from coral that allows them to glow under certain types of lighting conditions. Despite their modifications, they still breed like regular zebra danios.

  1. GloFish

    • GloFish are zebra danios with one additional gene that allows them to absorb and re-emit light in various colors. Among egg-layers, zebra danios are one of the easiest aquarium fish to breed; you only have to worry about the parents -- or other fish -- eating the eggs. They can be triggered to spawn frequently.

    Frequency

    • GloFish -- and all zebra danios -- can spawn multiple times throughout the year. A mature zebra danio with a steady supply of food can spawn every other week. On top of this, Glofish are sexually mature at 3 to 4 months of age, meaning they can go through at least three generations per year. Additionally, wild zebra danios school for protection, so GloFish need to be kept in groups of at least six to feel safe in an aquarium. Because of this, a group can almost constantly produce young. Every spawn consists of up to 100 eggs. However, adults will usually eat most of their eggs and baby fish unless steps are taken to prevent this.

    Breeding Setup

    • If you want to breed GloFish, they need minimal accommodation. You can spawn GloFish in an aquarium to 5 to 10 gallons. Fill the aquarium halfway. Provide filtration with a sponge filter, and adjust the water flow to avoid strong currents. Most importantly, you should include a layer of marbles of plastic spawning grass -- available at pet shops -- to protect the eggs from the parents. The young need to be fed on tiny foods like paramecium cultures.

    Patents

    • It is illegal to breed or sell GloFish without a license from their manufacturers. This is because the modified genes are patented. Patenting a gene has some controversy, but since the genes are patented, no one can legally sell GloFish without paying royalties to the company that produces them.