seconded with bro steven abt bio-ring.Yes it dos'nt spike no3,and jus to add,it must be totally submerged without any of it exposing to the air.I'm using bio-ball and the PH mantain at abt 8.4 in the day and 8.1 when lights off.Weekly addition of kal mix w/white vinegal and DI water.Also extra powerhead to blast from to right when lights off,cos my wavemaker will auto shutoff.Hope dat helps.