I totally forgot about them. Lettuce Nudibranchs. At one point years ago they were popular among club members here in Pittsburgh and the Cleveland club. I never owned one so can’t vouch for their effectiveness other than to say that other club members kept them and swore by them.
I wonder if they too would pose a risk to Randy’s refugium? I don’t know of they readily reproduce in captive systems or not.
I think it should be fine with enough prior research on the particular species. To my knowledge, the genus
Elysia, and essentially all sacoglossans, tend to have very specialized diets that consist of only a few select species or a genera.
I have seen reports of some species that can maintain a population in captivity, but for most species I believe it isn't possible because their veliger duration is too long. However,
Elysia crispata is supposedly lecithotrophic, meaning their veligers don't require food until they settle into baby slugs. If this is true, you could probably raise these like
Berghia. The hair algae never did grow back though. I suspect this was because the
Caulerpa finally took hold instead, so you might not need to breed them if they do a thorough job. A bit morbid, but they only like a year or two in the wild to my knowledge.
I hate doing this, but a minor point of taxonomy — they are sacoglossans, not nudibranchs. They are sea slugs though nevertheless.
