I did a bunch of this in my main pond also before it filled. Made a bunch of huts made from various boards and pallets we has laying around (this was before I discovered PBF so did not get a lot of pictures to share). Spaced the boards about an inch to two inches apart, some as tall as about 3 feet with ten or fifteen layers of boards. Also used a bunch of various tubing had laying around. Black plastic pipe, pvc pipe, grey plastic electrical conduit, etc.
Don't know if they did the trick or not, but we sure do have the FHM's.
I have linked to this video before, but this is where I got my original inspiration.
Fathead minnows breeding like crazy! The FHM will use any solid underside they can find. Rocks, logs, red Solo cups, pallets, pipes, etc. Any open underside will work, but something that can give them cover from larger fish gives them a chance to spawn without being eaten.
