well my nitrates have been up at or above 40 ppm for a while. i cleaned out my bioballs realy good, and cleaned the entire tank. i did a big water change, and bought a product called algone that is supposed to reduce nitrates. it has done nothing so far. i really need to get this under control. should i try that kent nitrate sponge filter media?? also, does carbon help in nitrate reduction? should i add some LS if my sandbed is only a couple inches deep?? thanks for any assistance!