Since isopods do not become giants in general, it concerns adult animals with this size. There I recommend that you simply feed the male isopods so that the reproduction rate is not reduced. You can find an article about the sex determination of isopods in my blog. Now to my recommendation. I know many breed Porcellio hoffmannseggi with these claims, but in my opinion the species doesn’t reproduce fast enough for some of you.

Also, the development time is simply much too slow for it to be considered a feed animal. So there is only one species on my list, Porcellio spe. Sevilla. They grow up to 2.5 cm, sometimes, the older males even get a little bit bigger. They reproduce very fast and much less complicated than the P. hoffmannseggi. With a regular protein addition you have a perfect food animal with this species.