got undergravel filter. i plan to take out my gravel and replace it with sand. i will add amquel in the sand for the amonia and nitrate. what about the good bacteria in the gravel? HELP.
Bethany;1971570; said:sand is not recommended at all for undergravel...
if i change my gravel or sand i keep the original decorations and don't clean them, since they retain a little bit of the bacteria just to help it out, really don't know if you're supposed to, but it's worked for me lol