Do I need to PH when I water with Pure Blend Pro in Coco?

Some clones in botanicare readygro coco mix.
I got the pure blend pro grow for nutrients, and I am mixing that with RO water.

I am wondering at what strength I should mix the nutes, and if it is likely that I will need to add ph up or down?
I don't have a ph meter so I am a little sketched I will kill the plants.

When I transplanted the coco into the mix I watered with plain water because I wasn't sure.

I'm just so scared, I'm wishing I would have stayed with soil which is easy as pie and worry free

depends on water your water ph is and the ph of your juice.. i think your gonna have to add calmag to stabalize the ph of the coco.. you would only add ph up or down if the run off is to high or to low. Or when your mixing nutes. but most hydroponics nutes are bh balanced. I do not know what the ph of coco is, i havent used it. Just check your ph a half an hour after add nutes in the reservioir.