Between my oversized Algae Scrubber and water cahnges I managed to get my nitrate and posphate down to zero, I even lost some SPS soral in the proces so now I am dosing Nitrate alost daily and Phosphate about once a week. I have a 40 breeder, bare bottom sps only tank with a good amount of fish, 2 cromis, 2 clowns and 2 butterflyes that i feed about 2 cubes of frozen and a pinch of flakes daily however, that doesnt seem to be enough to keep my nitrate and phosphate unless i dose. My scrubber is about 30 square inches lit on both sides, water fall about 70galons per inch flow, with 5 red and one purple Cree leds on each side at 750 mA that are on for 18 hours a day. No skimmer, no gfo, no carbon, bare bottom sump. I used to have problem with phosphates leeching out of my rocks that build up in them by not cleaning my send bed for over 2 years when i did the DSB thing so I got rid of it and went with the scrubber which I oversized so I can get rid of the phosphate faster. Anyhow my main concern with the dosing is that I want to keep my phosphate as low as posible but I am not sure if my scrubber will grow alage if my phosphate was say 0.01ppm, I am worried I might get a nitrate problem since my nitrate goes up if my phosphate test 0 for 2 days in a row. I use salifert test kits for the nitrarte and phosphate. I've ben keeping my nitarte around 0.5 -1 ppm and when the phosphate drops to 0 I've been raising it up to 0.01- 0.03 ppm I dose brightwell nitrate and seachem phosphate or food garde trisodium phosphate instead of trowing more food because I don't want to have a bunch of uneaten food floating around, my fish seem to struggle eating more than one cube of food at a feeding. On the other hand I like the dosing since I can control my levels to a precise level which is kind of nice, therefore I am not planing on down sizing my scruber. The only issue that i have with the doising is that i got about 1/16 of an inch hair algae on some of my rocks and some on the bottom and back glass of the tank. Hoping it will go away once my scrubber recovers completly from the lack of nutrients before i started to dose and I wont have algae in the tank. My new fargs are loking real good, keeping color and some have new growth so no complains about that.