Hi,

Sorry to bother you again with my "coconut based compot" stuff !
I'm still struggling with the mineral disorders that cocosubstrates can do.

After reading that coir could give off potassium, I'm now wondering if I can still use my regular fertilizer without risking a potassium excess and a calcium/magnesium deficiency.

I've seen that there are specific A+B fertilizers targeted at cocosubstrates, but surprisingly they seem to have a rather high potassium ratio. This doesn't make sense !

Could you explain the difference between coco specific fertilizers and regular ones ? Is it risky to keep on using a regular fertilizer (mine is N=2.2/P=1.3/K=2.1) ?

Not too risky if you use small amount at first and then gradually build up to regular dosage.