I was dosing nitrates [zero'd out - and zero'd out phosphates as well] and I decreased my refugium light period and the phosphate came up as I continued to dose nitrates. I also have always overfed, and I ran my skimmer with the collection cup draining back into the tank. I even overstocked my tank and couldn't get nitrate to raise. Once I shortened by refugium time enough, they began to balance and I could control nutrient levels by upping or dropping the light time.
Everyone has issues with too high of nutrients, but i've had too low since the start in this hobby =S
Everyone has issues with too high of nutrients, but i've had too low since the start in this hobby =S