Heya! So I got some nitra-guard bio cubes from Orca from one of my friends, and I've heard amazing things about them! However, after copious amounts of research I am still clueless as how to use them! I have a small 10g tank but with nitrates from 40-80ppm (tap water). I have attached a picture of my filter and it does a little over 40 gallons an hour. How can I add the large chunky crystals safely to my small-ish filter? How much should I use? Im just really confused about the whole thing Thanks in advance!