The spools that our hydraulic hose come on for our shop are heavy plastic and I have saved up quite a few of them. Looking for ideas on placement of these. I have considered putting them out one at a time, replicating a stump. I've thought about stacking them and making some sort of pyramid type structure and I've thought about putting them on a pvc "trunk" weighted at the bottom to get them up off the bottom of a lake. The spools are around 18" wide and 22" tall. If you had these, how would you use them for fish structure?