When buffering with Sensi CalMag Xtra, I do it first for 8 hours, using 60 ml in 30 liters of waterr at 25 *C with a total pH of 7+.
EC is then around 1.2 - 1.8.
After 8 hours I let the two AutoPots with Coco drain, then repeat the whole process with a fresh batch of CalMag.
I mix each 5 gallon batch of buffered Coco with Perlite separately, makes the end product more refined and easy to work with.
Half a brick of Ugro Coco Coir is enough for two 5 gallon pots, especially after adding Perlite and drying a short while..
The end result has a perfect EC of 1.2 and pH is 5.8.
When I do it this way I have not experienced any CalMag deficiencies, the Coco/Perlite gets a freshly made batch of Canna Coco nutrients. A light feed contains Canna Coco A and B plus Rhizotonic.
If the end result has a higher EC than wanted, run some pH correct water till runoff is as wanted.
Information I use comes lightly modified from cocoforcannabis. A great website for first time users and more advanced users. Dr Coco knows his shit!
Medium is now ready for my hungry AK-47 and OG Kush Autoflower girls.
Happy growing. 😀
Regarding EC levels.
Seedlings 0.4 (400) or less
Vegetative 1 (1000) or less
Run pH correct water to lower EC to required growing phase, this would mostly be Seedling stage.
My Coco /Perlite mix is for Seedlings this time, I will lower the EC levels to around 0.4 with water. Checking the runoffs before introducing nutrients.