Yeah, I used rapid rooters or rockwool with no problems.rapid rooters will work fine, what problems are you having with the wool?
Are you putting a layer of hydroton on the bottom of your cup below the rockwool so the wool doesn't get oversoaked?
BRO check out my diy hydro thread in this section.PEAT plugs are by far the easiest to use in this setup.Wool can be used to.But the plugs come already pre-phd. So you dont have to worry about pre-soaking and oversoaking issues. I just got done explaining the entire process.i can't seem to get rockwool down, can i use rapid rooters in this set-up? does anyone on here use them for just a typical 5 gallon dwc bucket grow