Appearently in my earlier post there was some confusion about my frog and his living quarters. I am sorry I wasn't more specific. Thanks again for all the advice. It was great, and I found it very helpful.

My frog is an African Clawed Frog, he lives in a fifteen gallon aquarium with a goldfish that is almost as big as he is. He has no land, just water. I leave about 1 1/2 inches of room at the top so he can come up to breathe, and eat. I hope this clarifies things.

I was just asking about the gravel in the bottom of the tank.

Thank you again. You guys are great!!!