for a frog only tank, no land is needed, sand substrate is prefered, lots of caves, hidy holes, tubes etc are good ive found, as well as plants. 3 main ways to feed them, with sand substrate you can just drop the food right on the sand, it wont sink between the gravel (as they isnt any), or use a shallow dish to place food in, frogs soon learn wher the food is, or use a pipet or turkey baster to suck up the food and drop it near/next to the frogs for them to snap it up. all feeding tactics work fine, but the first 2 wont usally work with other fish as they will eat them first. i would say 10-12 frogs in a 10gallon, its 1 gallon per frog minimum, but as they are little waste producers and no other fish in the tank, you would get away with a couple more.
as for other tank mates, dwarf cories are suitable, but being bottom dwellers, probally not the first choice, i have cories and frogs together no problems, but i do have to make sure the frogs are getting there share of food.
bettas are another possability, 1 male betta would work fine, even with 1 male betta i would say you could still get 6-8 frogs aswell.
or a small shoal of fish, neon tetras, cardinal tetras, other small tetras or small rasboras would work, having a group of 5-6 fish and 4-6 frogs would stock the tank.
or even another fish such as sparkling gourami, dwarf gourami, other small gouramies, or a few endlers would work.
just remember, what ever you have in that tank, keep up with regular water changes, and tank maintance and everything shoudl workl out fine, cycle the tank first too.
