I have a 20 long, thin layer of Flourite (?) gravel with driftwood and two powerful filters (capacity about 4 times tank volume). I need to stock it and will be switching it out with my other tank this Saturday if my parents can help me lift the other one and get it outside. I am putting in used filter material to precycle. I have six or so guppies going in for sure, but not sure what else! I love cories, otos, and schooling fish but really want a good centerpiece. The driftwood is piled in the middle of the tank and clear space all around as it is currently arranged. Please help! I don't want live bearers besides the guppies and MAYBE a single platy. Nothing too exotic as I just have a Petsmart, Petco, and small lfs with limited choices. Thanks so much!