What I do is put a shallow layer of hydroton in the bottom of your net cup put your RW on top of that in the center, and then fill around the cup with hydroton to hold the RW in place. To start my seeds, I put them in a jar of water in a dark, semi-warm place and leave them for 24 hours (I don't let the tap root come out at all...i just watch for them to slightly swell and for the rim to look like it's getting wider). Then I put them in the RW and let them finish germinating (you need to get them a little deep...about 1/4 inch or so...) It is better for it to be deeper than to shallow; one guy on here didn't take my advice on that and ended up killing his plants (if it is shallow the tap root gets confused cause it is surround by light, so it gets crooked, grows out the top or side, and then you have to try to turn it the correct way and it dies). Give it about 2 days for the cotyledons to emerge and the shell to fall off, and another 3-4 days and you will have a nice set of true leaves. At this point just go ahead and slip your neoprene disc around the stem ever so gently and you are finished. A lot of people don't use nutes in the water during this stage, but I do. I do because as soon as those true leaves emerge, it needs dilute nutes. Sometimes this happens in the middle of the dark phase or when you aren't around, and thus it is starved until you decide to feed it. I can get my plants up to 4.5" in 7 days, by simply adding a dilute nute mix to the water. The argument against it is that the shell already contains nutes, and this is true...but only enough for the cotyledons to emerge and the root to tap out...then it's finished...the plant will stall...think about nature...that plant has nutes available from the minute the seed touches the forest floor....it may not use them just yet, but when it decides to eat, they will already be ithere for it.
