My marine tank is looking pretty dismal — the coral are chronically unhappy and there’s way too much algae. For a while I was secretly nurturing hair algae so I would have an excuse to buy some Elysia slugs.
Elysia are another great example of the oceans totally messing with my expectations about what’s a plant and what’s not — these slugs eat plants and, in eating them, become like plants, sequestering the chloroplasts and photosynthesizing most of the food they need.
The slugs did a great job of looking good but didn’t make much of a dent in the algae. The adults I got from Florida laid lots of eggs in the refugium and then promptly died (no idea if that’s part of their plan or a judgement on my poor aquarium-keeping-skills) — I shot a lot of video of the eggs and veligers and now have at least two, possibly three, tiny slugs growing up in the main tank.
There was really no special care involved — the veliger stage is transit-only so they don’t need to be fed until they settle and start grazing. I suspect that anyone who keeps these slugs in a system without too much turbulence or mechanical filtration is breeding them whether they know it or not.
Here is a short talk I gave about my slugs at a work event. I’m always asking people to give more presentations about their non-work-related eccentricities so it seemed only fair.