I don't use brick coco because I feel the quality is better in the bag.
The few times that I used brick coco, I first hydrated it with tap water.
Then I rinsed it in a bucket of clean tap water.
I put a couple of handfuls of coco in the bucket of water at a time, swish it around, then scoop out what floats.......the powder sludge sinks to the bottom.
Once I have a bunch rinsed and scooped out I place it in a bucket and saturate it with 1/4 strength bloom nutes ph'd around 6.0 overnight.
Hope that helps.