Well, my system has honestly been neglected for the past 6 months and my sump has become somewhat of a nitrate factory. I cleaned her all out, threw in some BioClean, PhosBan, carbon and brought 250ml of Ecobak online. Keeping my fingers crossed!! My spa have all browned out, the only ones maintaining growth and color are my montis....my lps and nems have been uneffected. Ill be interested to see how quick my np levels drop.