I'm in the process of getting a pool built.  18x36 vinyl.  I'm wanting to pour footings and double thickness of concrete on the north side of my pool and lay a 15x10 out of block then seal and tile and have it spill over into the pool. 2 blocks high with a mouth with rock that extends so water falls into pool.  Can this be done?  Seems simple in theory but I'm sure someone will tell me why it's a bad idea. Has any of you done this or think I can make it work?