i have never tried to use gravel over potting soil, but i have used sand. have not had much of a problem with brown water, b/c the sand keeps the soil in place. and i think the plants do really good. have it in a low light tank and a high (i know it is against her philosophy), but once the plants take root in the soil, they go crazy.
as far as the soil is concerned, i figure the cheapest you can find, the better. tends not to leak out as much stuff.
as far as the soil is concerned, i figure the cheapest you can find, the better. tends not to leak out as much stuff.
