dens and runs...probably my most product set in open water, too.
floats definitely perform better if put out a couple weeks in advance, prebait them. I use more apples, carrots, and potatoes, or cattail roots and shoots if available, and a good rat call or food lure. I move floats that don't show signs of visitors until they start showing some sign of use. Run floats without traps at them for a couple weeks like that, rebaiting where needed, until they are all being visited and used, then add traps and start cleaning up. I avoid using corn on my floats to avoid waterfowl. I also use a lot of long grasses on top of floats if I build them with roofs so that they look more natural and less open to theft. I also found if I anchor them with a couple bricks on a long wire, and put them out in deeper water but close to natural food areas such as cattails, etc. then I got fewer coons bothering them, too. Front or rear foot caught coons, even on drowners, can really destroy a good float set.
Anyway, just some info I learned the hard way with floats...