I'm using a 30 x 22 x 22 tank (+ - 60gal tank) got a few big blue pebble in the one corner with a plastic plant and some moss drifting on the surface. Most of the bottom of the tank is clear (no pebble - only the glass bottom). I put the filter off when they build their nests (normal sponge filter - nothing fancy) and the water is constantly between 81f and 83f. I clamp a piece of bubble wrap (15cm x 15cm) to the side and make it drift on the surface - they build their nests under that. I find that helps keep the bubbles moist. I also wrap cling wrap over half of the top of the tank to sort of close it (also just to prevent a draft and keep the air temp constant)
I feed them
brine shrimp, bloodworms, daphnia, pellets and flakes (mostly the live or frozen foods - I don't like the dry foods).
for the fry - well for the life of me I cannot get microworms, but I found a guy who use to breed Bettas and he gave me a container with some stuff that is similar to micorworms - but they are not alive. I don't have the name on me unfortunately - I'll you tomorrow what it is. And he swears by it.