Thank you ,yes the biopellets are definitively working for me.My suggestion is to start slow,because they can strip water of nutrients very fast.I use original NP pellets mixed with WM EcoBack pellets in TLF 550 reactor with very little tumble.I use MJ 1200 to power the reactor.Started with 250 ml.,after 2 weeks added another 250 ml,and finally month later another 250 ml. for total of 750 ml.My PO4 and NO3 are undetectable.After about a month I noticed my corals to fade in color,so I started to feed my fish more (2-3 times daily) and I am adding amino-acids and Lugol's solution. Within couple of weeks colors come back even more vibrant than before.Some people reporting negatives with pellets,but so far they working for me.My tank is turning one year this week and color and growth are phenomenal. Also make sure you have adequate size skimmer to export the bacteria,I have outlet from reactor in front of skimmer pump.I do use small amount of carbon to keep water crystal clean,but no GFO.Good luck,hope it helped.