Autopot ph problem

[Martin1980]

Having problems with ph drift. Growing gorilla auto strain in cocotek coco-perlite mix 70/30, 15L autopots. Using airdomes in pots. Nutrients are Silica 1ml per litre, CalMag 1ml per litre, GHE Flora trio series at 1/3 of recomended dose ( Micro bottle is for hardwater). Water is RO. Started to see calcium deficiency for the last week. It's 4th week from seed. The ph in the tank always drifts up, if in the morning it's 5.8, in evening it climbs to 6.1-6.4, the ph in the trays is even higher 6.7-6.9. I'm using submersible pump to move the water for 15min every 3 hours. Any idea why the ph keeps climbing up so quick?

[Woodie2010]

Hi, I use autopots also, which are fed by my 100ltr tank and I have a submersible fan in my tank circulating the water/nutrients that's on 24/7 to try add abit of oxygen to my water/nutrients and to make sure they mix correctly. I also use airdomes in my autopots. My Ph always drifts abit slightly in my 100ltr tank and my autopot trays will always read a tiny bit higher in the trays so when I add all my nutrients I make sure to Ph down to about 5.4-5.6 that way the ph in my autopot trays usually end up about 5.7-5.8. I check my water/nutrient tank everyday and it generally rises slightly which is a good thing but I never let my main tank get above ph6.0 cause that generaly means my autopot trays will have a Ph of 6.3 or higher. Maybe leave your circulating fan in ur water/nutrient tank on more often to see if that helps balance the rise of your Ph. Either way always adjust ur Ph with some Ph down if gets abit above the 6.0 range 

[Martin1980]

What nutrients are you using?

[Woodie2010]

I use canna products, Canna Coco A+B - Cannazym - Rhizotonic - Boost.