Oooh, a waterfall would look pretty cool...not sure if I have the skills to pull that off at this moment. Right now, I just want something that is easy to maintain but is safe and fun for the toads. I always try to keep my tanks as natural as possible, so definitely no pink or purple gravel for me! Black might be good, especially to offset green plants....I will see what is the best bang for my buck. I have a small underwater filter right now, but I'm not sure if it's doing much....I might have to upgrade on that a bit down the road. One thing at a time. First: lower the water; second, get some more plants; third, get some gravel or sand. That will keep me busy for now!!