I am setting up an aquarium (65 gal) where I'll keep angelfish and maybe a few clown loaches and I'm planning to have live plants. I like the way sand looks when it is used as a substrate, but I'm worried how will the live plants hold on to the sand? I thought maybe to put first a layer of gravel on the bottom, and then cover it with a thin layer of sand. Does anyone have any suggestions about this? Thanks in advance!