Quote Originally Posted by John View Post
Jim's approach is the normal way. I prefer to use LECA instead of egg crate - I find the egg crate unsightly.
It's true that the eggcrate needs to be covered in some manner. LECA is a great way to go as well and I've used it in combination with some eggcrate in the center to have a larger overall volume of water in the system. All of my vivs have flowing water features and I have to balance the water flow, water storage volume, and water level in the system. If the water flow is too high for the storage volume, you will get lots of gurgling from the pump. If the water level is too high, it'll keep the substrate wet, which isn't good for certain frog species. If you just want enough water flow to keep it from getting stagnant, then the storage volume can be lower. The only disadvantage of LECA is that it displaces some water and reduces the storage volume.