I'm about to start putting up forms for my new pool walls. These walls will be poured concrete, with 1/2" rebar, 50" tall, with the wall 8" thick. I have three skimmers to put in. They are Hayward SP-1082 skimmers. Is it best to place the skimmers so that the front plastic opening that receives the water, is flush with the inside of the pool wall or is better to set it back so that the whole skimmer is separate from the pool wall with the front plastic opening that receives the water, up against the dirt side of the wall? Of course I would have to support the skimmer with a separate poor of concrete so that it is secure but should there ever be a problem with the skimmer in the future, it would be easier to replace. If that is the best way to place the skimmer, how does one make sure that there are no leaks where the plastic opening meets the outside of the concrete wall?