As for plants, I use sand. Play sand from Home Depot. It costs 2.99 for 50 POUND BAG!!! Its sterilized also. Only thing is to wash it very well to remove dust. I use about 1/3 to 1/2 a bag, place it in a 5 gallon bucket and wash it till not more dust settling clouds the water. You can stick a garden hose in the bucket at the bottom at an angle to swirl the sand. I let it run for 30 minutes, draining of excess dusty water. Also this leaves back heavier sand grains. I place my filter pick-up 1 to 1 1/2 inches from sand with a bubble wand as close to the bottom next to the filter pick-up, with out getting air into filter. This draw all the waste settling on the sand towards your filter. Sand keeps fish waste from settling into it, filter picks it up instead. Also plant roots pretty well into it in my tanks. You can place gravel on top of the sand to prevent sand erosion in high current areas to keep plant roots covered. I have in a 25 Gallon High, 9 stalks of Dark Green Cabomba, 3 light green Cabomba, 4 Red Ludwigias, 1 Giant Amazon Sword (Broad Leaf), 3 dwarf lilly-hybrids, 2 hardy aponogeton plants, 2 banana plants that grow extremely fast, 2 Sagittaria subulata, 5 Bacopa Caroliniana, and one type which I don't remember off hand (7 stalks). All growing with no problems. Some too fast for me to control. I also use "Plant Tabbs" to fertilize the plants with 12 hours of light. *crazysmiley*