In simple terms, a triploid fish is merely a fish that is sterile. Triploid fish have three sets of chromosomes, unlike a fertile fish that have two sets of chromosomes (a diploid fish). Triploids are common in many industries; Seedless watermelons are triploids, as are bananas.
Can triploids reproduce?
Triploids, in particular, are characterized by the problems of chromosomal pairing and segregation during meiosis, which may cause aneuploid gametes and results in sterility. Thus, they are generally considered to reproduce only asexually.
Are triploid plants fertile?
The natural triploid is 80 percent fertile, and morphologically similar to A. shortii. The unexpectedly high fertility of the triploid hybrids may be due to any one, or some combination, of a number of factors.