I have 3 of the little things (I believe they're all female) and I can't really feed them the same way I feed my fish. I tried using algae wafer and they didn't really go for it. Do I even need to feed them? So far they seem really content in my Java Fern, where they can really hide from anything else. Occasionally they'll come out. How do I tell if they're eating enough? And how do I feed them? I'm going to get cucumber soon so I can put a slice in there.