A while ago I started experimenting with different caps, sizes, substrates, and so on to see how the different setups affects the RFAs (e.g. do they seem “happier”, move more often, try to escape, firmly foot, etc.) and whether it mattered. I drilled holes in one of each size to allow more flow through the cap and around the nems. It also had the benifit of draining the caps of water when you picked them up. The RFAs don’t seem to care if there are wholes or not as long as their is enough flow moving over the top of the cap.
When moving them to the display, the gravel in the end cap makes things a lot easier. If they attach their foot to the gravel, then you can sometimes just pick up the chunk of gravel and move it to the display in one swoop. They will usually dump the smaller gravel and pick some better real estate in the tank after a a couple hours.
For ones that stick to the cap itself, you have to peel them off extremely carefully so you don’t hurt their foot (it will often kill them if their foot is wounded). You can use your fingernail starting *slowly* from one side of the foot to separate them. Others use things like an old credit card. Personally, I am overly cautious about hurting their foot. So if gently sliding under their foot doesn’t budge them, I stop trying. In those cases I just get a small container or glass bowl with some water in it and turn the cap upside down suspenders over the water. After a bit (can be a few minutes or even an hour) the RFA will voluntarily detach from the cap to seek the water below.
If you have a really stubborn one, you can put them in a bin or water with a small powder head or pump. Put the cap on its side and have the pump blasting straight on the RFA. The stubborn ones usually get mad after a few minutes and will finally release their foot to move
