They are sucking the nitrates so I am dosing nitrates in to keep them stable for the sake of coral growth and dinos. When I let them bottom out the tank gets covered in a brown slime when I raise it back above 10ppm or so they disappearWhat I am wondering about is the nitrates. With all that GHA sucking in nitrates I would think they would be low, yet they still measure at 20. Where is it all coming from?