I really f*cked-up... The PH meter i used was not calibrated for more than a year (lazy grower) and when i finally did i found out the ph in the slabs was ph4.5
Its works perfect if you like to grow colorful plants, but sucks big time if you want big healthy productive plants. Considering they had this super acid medium
they are still doing pretty well. At least the last few weeks since i added an extra SpiderFarmer SE3000, not only for extra light but mainly to get the temperatures up.
We had 2 very cold weeks in the Netherlands with lots of snow and ice so that didn't really help either. Now i am just gonna try an experiment to see how much thc
i can get on it.