Nudibranch question

[seanmcknew]

So I bought this nudibranch. I didn't research before I bought it...(maybe a big mistake) the guy at the LFS said he eats algae but I don't see anything that resembles a algae eating nudibranch. Here's a pic I don't want him to die and I want to take care of him properly some I'm asking for advice.

[Squid]

They eat mainly sponges but I have seen them eat algae as well. just beware, if he dies he will nuke your tank. (I know from experience, mine got chopped in a power head)

[CMD2213]

Purple nudibranchs feed on barnacles, tunicates, bryozoans, and flatworms, as it has a carnivorous diet. Diet supplements will be enough to feed the nudibranchs, so they will need the above mentioned foods available which makes it difficult to maintain. Thus it is only recommended for an expert aquarist. Found this.