Syreptyon
Chameleon Enthusiast
Most if not all of the cool nudibranches have pretty specific diets don't they? I can't remember why they weren't seen in the hobby all that much.
So I've been really interested in nudis and seaslugs since getting into the saltwater hobby. Apparently the difference is that nudibranchs are carnivorous, whereas seaslugs are not.
Some nudibranchs are actually really dangerous to fish, inverts, and coral and will actively hunt them. Some of them are poisonous or able to release toxins that would decimate the tank's stock. Sea slugs are easier to keep generally, but you're right that they tend to have very specific diets. I had a pair of "lettuce nudibranchs" (although they're technically sea slugs due to their diet) and they would only eat one specific type of macroalgae. Also they will readily get sucked into powerheads... wavemakers.... filter inflow.... it's like they want to kill themselves