HI guys, not sure if someone can offer advice, ive searched ages on this topic and find lots of info but none of it giving me a real solution. Im running a 80Litre brain to two 50L pots of coco, plants are very healthy and growing really well but the thing thats bugging me is every day my ph jumps up. in my Brain i have a water heater set to 20 degrees, water pump and 2 air stones from an air pump, i have cocos A+B, roots excelerator and drip clean. I have my air stones and water heater on a seperate timer that comes on for an hour and half before the plants get fed, after adding fresh water and nutes i adjust ph to 5.8 and i leave it say over night and the next day just before the plants are due to be fed i test PH again and its up over 6 (roughly 6.3 sometimes).. ive tested and left the air stone off and the ph doesn't change a bit. Ive spoken with a few different hydro shops and they all say they use a similar setup and never have ph jumps like that, a slight increase over time is normal but not that high. But they have never heard of air stones causing that issue. Has anyone else had this or found a solution? im going to stop providing air to the brain and just put a pump in for circulation of the nutes but it goes against my basic instinct of providing air to the water solution.. Any input is greatly appreciated