Coco pH runoff

Hey folks,

I have been researching this question all day and I've been struggling to come to a conclusion as I have read a lot of conflicting info.

I am trying to prepare some coco to plant seeds in. No matter what I do, or how many flushes my coco gets, I can not get my pH run off to go below 7pH, usually 7-7.3pH, and what's going in is always ~5.8-6.0pH. I've even tried a fresh batch of coco, no nutes, 0.5L pot, flushed over 10L of RO water pH'd and still the run off does not change. I've tried flushing 4.0pH water through it and still get 7.0 or higher runoff.

Is this a sign of some kind of buffering in the coco I am using? I don't have permission to post links but it's called Brunnings Coco Power Peat Brick. Mixed with 30% perlite.

The PPM of the run off is fine, very low matching my RO water but the pH is concerning me. I can't understand why the pH of the run off is so high.

Can anyone explain to me if this is normal or something to be concerned about?
Would you use this coco or should I go and get some canna coco instead?

Thanks,
Outlaw

Sounds it has peat in it and buffered for use as a soil additive. Bagged Canna coco works well for me.

Thanks I think you're right there is something in there fucking with the pH.
I'm going to get a bag of canna coco today and try the same thing with it, just to put my mind at ease.