I've seen this topic debated before, and was looking for a recommendation. I am going to install a Hayward 24" sand filter, S244T, and wondering if I should put a layer of pea gravel in before the sand. The instruction manual doesn't mention this at all, but does recommend that I fill the tank 1/2 full of water before dumping in the sand. Are there benefits to the gravel method, and can the gravel harm my underdrain laterals? Also, the instructions state to fill sand to 6" from of filter - is this a trouble free pool recommendation also? Thanks in advance for your feedback.