Sorry, I though I had said but, I hadn't use egg crate in a tupperware container lots of surface area and easy to get out of your way to catch them. I don't know if your mandrin will EVER eat other foods most of them won't . However with the proper pod breeding operation you shouldn't have to worry about that. I'd run two plastic tubs full of them ,"split a culture that should do the trick" and you'll have more than enough . You other fish will enjoy them as well they are pretty much the perfect food for lots of s..w critters if you raise them correctly.