I check the ph everyday and every time I check it, it always is really high. I bring down to 5.5 and sometimes it goes up to 7.0 when I check it the next day. How come?

dude think about it when you add nutes to water your ph goes down
therefore if your ph rises your plant or plants must be consuming the nutes
if your ph rises your plant or plants are drinking more water than nutes,
if you have the perfect mixture your ph would be more stable.

how big is your resavoir ? a bigger resavoir helped me out but i still adj my ph every 24 hours or so i never would let it get over 6.5 sometimes it would go 2 days without needing adj.

sounds weird but distilled vinegar will bring your ph down i use it and it works great its cheap also


good luck with your grow

nute up-take will raise the pH slightly higher,1.5 is a little extreme,it might have to do with the rockwool not being stable enough,if it's not stabilized in a pH water solution of 4.5 for at least 24HR's,it will still release alkalines in the reservoir afterwards,next time you stabilize it just let it drainout on a cappilary mat,do not rinse it ,if you do rinse it out, it will defeat the purpose....bonbon

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bonbon, I don't know what you mean about drainout on a cappilary mat, and rinsing out. I do soak the rockwool but the water was ph 5.0 and I didn't check it after I took out them out of the water. Thanks for you help and also thanks to jimmy. Willow