Take a small length of 1/2" PVC, drill a hole in it and tie fishing line or airline tubing to it. Attach the line to the outside of the tank, ie., tie it to something, a suction cup or whatever, so that the tube inside the tank is easy to pull out. Now take your nori and wrap it around the PVC, and an elastic that you criss cross it over to hold it down.
Once you feed your fish this way, you'll never go back to a clip, I promise you. It's a more natural way for them to pick at it, and they'll get more of it, and you'll have less floaty bits floating around. Ie., it fouls your water less, they get more of it, and you'll have way fatter fish as a result. I guarantee it.
Ok, crappy picture but to give you an idea of what I mean, look to left of my tank here (where the tang is swimming towards).
PS. Anything the fish don't get (which isn't much anyhow), if you have urchins or seahares or abalones, they'll polish it off at night. Everybody gets some this way and very little ends up wasted.