Hmmm...my bag said to add the liquid into the tank. It's not a 'black water' mix...cuz the liquid is almost crystal clear!
In an established tank, there's no need to add it. In a new, uncycled tank, this stuff's supposed to remove the need to cycle.
I changed out from flourite to Eco, used 2 bags in a 20gallon, with all the 'juice' and have 0 problems, not mini-cycle, and crystal clear water.