OohFeeshy
It's only forever; not long at all...
The Glofish FAQ page said:Do you have to add a fluorescence gene to every fish before it hatches?
No. Today's GloFish® fluorescent fish are bred from the offspring of fluorescent zebrafish that were originally developed several years ago. Each new GloFish® fluorescent fish inherits its unique color directly from its parents, maintains the color throughout its life, and passes the color along to its offspring.
That's a jolly funny sterile fish.