Since your into aquaponics, I've got two ideas for you. If your fish are tropical, then you already have the heat and humidity you need for cloning, no dome needed.
1- remove enough media in your growbed to expose the water level on the top of it's cycle. Place your tray of rockwool and clones right on your AP medium. Done. Each time the water level touches the bottom of the tray, the cubes will wick up water. Each time the bed drains, the cubes will drip water and pull in O2. Roots pop quick, within ten days, so be careful to remove them before they anchor in the growbed. AP water is perfect for cloning in respect to nutes, temp, and beneficial bacteria.
2- drop an airstone in your fishtank, and place a vertical PVC pipe over it, terminating at the water line. The bubbles coming up the tube will create an overflow of foamy water that spills back into the tank. Pick a bouquet of clones and drop them in the pipe. You will have a bouquet of bare root clones in 7 days.
Personally, I use a razor blade to barely slice thru the outermost skin on the bottom 1-2" of the stem, making a 2-3 vertical slits. A column of roots will erupt from each slit, and root mass grows quicker than non-slit stems. It's us a good idea to pH your rockwool with pH down, as per instructions. Lemon juice (citric acid) and vinegar, are anti-bacterial and detrimental to AP. Not a big deal, just not a good practice. Soil starter plugs are fine in AP, I use them all the time. In fact, rockwool is my least favorite cloning medium, of course bare-root is the best! Good luck
1- remove enough media in your growbed to expose the water level on the top of it's cycle. Place your tray of rockwool and clones right on your AP medium. Done. Each time the water level touches the bottom of the tray, the cubes will wick up water. Each time the bed drains, the cubes will drip water and pull in O2. Roots pop quick, within ten days, so be careful to remove them before they anchor in the growbed. AP water is perfect for cloning in respect to nutes, temp, and beneficial bacteria.
2- drop an airstone in your fishtank, and place a vertical PVC pipe over it, terminating at the water line. The bubbles coming up the tube will create an overflow of foamy water that spills back into the tank. Pick a bouquet of clones and drop them in the pipe. You will have a bouquet of bare root clones in 7 days.
Personally, I use a razor blade to barely slice thru the outermost skin on the bottom 1-2" of the stem, making a 2-3 vertical slits. A column of roots will erupt from each slit, and root mass grows quicker than non-slit stems. It's us a good idea to pH your rockwool with pH down, as per instructions. Lemon juice (citric acid) and vinegar, are anti-bacterial and detrimental to AP. Not a big deal, just not a good practice. Soil starter plugs are fine in AP, I use them all the time. In fact, rockwool is my least favorite cloning medium, of course bare-root is the best! Good luck