Oh for future reference i used sulfuric acid (fishtank PH down) to stabalize my PH, works like a charm just make sure that yougo back every few hours and add more till you find it where you want it. Weird but it seems like Atomizer was right , i feel as if these pebbles acted as a stabalizer to keep from PH bouncing/ that or the nutes not sure. But once i got it stable id only have to add alittle bit each day to keep it there, and i mean like a half a top full for 9 gals. Hope this helps