I actually have 4 concrete blocks between the two pallets there, and everything is zip / rope tied together. I wanted the bottom pallet so that the weight of the concrete could disperse a bit over the area, and hopefully there should be space between the two pallets.
As far as the blue conduit is concerned, I took someones suggestion and drilled holes in the top of the arc to let the bubbles out. I also took another piece of advice I read on here and sprayed everything with fish fertilizer liquid and let it dry. Hopefully algae will take to it pretty quick.
I have a platform rigged up in the boat, so I just lift the 4x4's and the structure slides off the front. This one sank like a stone.
