Questions about ACF from a new owner

[HeartDeyna]

So I've recently bought 6 African Clawed Frogs and I have a couple questions. I've only had them for about 3 weeks and I'm keeping them in a 7 x 14 x 8 inch tank. Its got some river rocks and 2 hides but I don't actually know how to keep them properly considering the person who sold me the frogs told me I literally just need to keep it in some water and I can get away with feeding it rice (I'm currently feeding them aquatic turtle food since I have yet to find a store that sells frog food).

Firstly, I read online that the water level should be just about high enough the frogs should be able to stand up and breath. So right now I have about 2 inches of water since my frogs range from 1 inch to 1.5 inches not including legs. Is this correct or do I need 10 inches of water?

Secondly, there are times my frogs stand up with their head above water and they kind of "vibrate / spazz" and make the water ripple. If one of them start this the rest will follow. Is this a normal phenomenon? I tried googling it but didn't find anything because I didn't actually know what to search for. But I took a really crappy video with my phone so you can kind of see what they're doing.



Please help. Feel free to let me know what else I should buy for the tank or give me some general tank instructions.

Thanks.