i have a clean and clear 100 filtering system....use chlorine....definite recurring leak at main niche....letting water go down with system off....so far it has seeminly stopped at spa returns where sand use to come out and air bubbles of spa returns....i am in the process now of using 2 part epoxy at the niche and line the niche with it and especially the area where the low voltage wires exit into the conduit and in route to the low voltage light box...any help would greatly appreciated....hope i don't have to dig under the pool or spa...thanks.....i also have an air blower for spa-----does check valve and coupler have to be cemented in placed or can i leave it horizontally in placed by free standing?