I have a floating pond fountain for an aerator and I use 1' segments of the pool noodles spaced every 8' to keep the electric wire and the tie rope afloat. I zip tie the rope to the wire every 3'.
This makes it much easier to set it in place in the Spring and reel it in during the Fall. A one man job.
Otherwise, the wire and tie rope goes to the bottom, shortens up the distance I want the fountain at, gets gunked up, and is very difficult to send out and retrieve.