yeah...what he said. you must run new filter for a day or so down the drain, you ph should lower a bit after that.

ph for hydro 5.4-5.9 optimum is 5.8. run 5.8 through veg...then in week 2-3 of 12/12, after flower set...lower ph to 5.4 and raise .1 each week untill you are back to 5.8 and ready to flush. this will allow the uptake of elements more essential to flowering and back away from the uptake of nitrogen, which is consumed most efficiently around 6.2...peace