Water changes and light is all
i do. I suspect they will eat anything meaty as long as its small enough to fit into their mouths. For the most part I thing they are filter feeders.
I use a medicine dropper and fill it up with brine shrimp and slowly and steadily shoot it on the ric, they should react to this by closing up a little, if you are a little trouble due to flow you may want to unplug your power heads
Top of a 2 liter cut off. Cover the whole thing with the large opening. I drop food in small hole on Ric/Flowerpot/Zoa Anything you need to spot feed. Keeps fish from stealing. I also put a long streamer that hangs out of the tank on the top. (Keeps silly me from forgetting to remove) my 2 cents
Grue
i feed them at night with a syringe filled with cyclo-peeze and a fresh fish mix. a few smaller pieces on it's flesh, and it will take it in.
when i feed my ricordea often, they grow much faster, and look fuller.