A little big of trivia which was experimented with... I don't get the credit, but I trust Rob Toonen, and we were yapping about this. He told me nitrates were still being leached in lab tanks with 14 inch CC substrates. I trust him, because he said they were in his lab. And he was on his first Heineken! 
Anyway, couldn't agree more with this preaching, here. And Max, you haven't seen a rant, my friend! 
Good stuff. For years I tried to make CC work, using everything from nitrate sponge, to screaming at my tank. I went deep. 6" will do nothing. I tested nitrates higher than any chart could measure. It kept me from doing corals, but rock/caulerpa/fish were fine. I didn't even know they sold that stuff in stores. lol
Anyway, couldn't agree more with this preaching, here. And Max, you haven't seen a rant, my friend! Good stuff. For years I tried to make CC work, using everything from nitrate sponge, to screaming at my tank. I went deep. 6" will do nothing. I tested nitrates higher than any chart could measure. It kept me from doing corals, but rock/caulerpa/fish were fine. I didn't even know they sold that stuff in stores. lol
