I quit using those because the gnats are bad in my area so I went back to sealed domes with root riots, but I only had good success in water cloners using hormones and changing water every other day.
I would take Hormex #8 put it into a paper plate, wet the ends of the stems and roll in the powder, then dip into the cloner. Each water change re powder the bottoms of the stalks using hormex powder on a brush. Never dip your brush or plants into your bottle of rooting powder. Always put it onto a plate or something and then use it.