Looks the same as my little guys! Thanks for the picture, sums up my baby peppermint in the sump idea. I fed my mysis shrimp earlier, I put a piece of seaweed sheet in there and they look like they're having a feast. I'm thinkin if I get a decent population of them going I can just transfer a sump rock to the display as a little treat for the fish to find and munch on.
Chaeto might help in the sump, it gives the mysis a hiding spot, exports nutrients, and my yellow tang may eat the trimmings. Thinking out loud here, lol.