So far General Hydro coco has been the best quality coco in brick form, it had very low salt to the point where I can use it without rinsing. The guy at the hydro store told me he likes the brick NF coco, it is slightly cheaper. I have a brick and will be testing it soon. The texture looks good on the NF coco but the salt content needs to be checked. The NF cocos says it's prebuffered to prevent cal/mag problems.
The Roots coco sucks, it's hairy and had big chunks in it. It was at like 700ppm of salt.
The
Earth Juice coco is more like coffee grounds and has a good texture. It was full of salt 600ppm range. I found a whole bat in this brand once.
Oh yeah, soil to coco is easy. Take a soil plant and rinse the roots off and soak them in B1. Then transplant into coco. After a few days, it will take off.