I have a waterfall with flagstone on top, and long stone beam on the front face. The beam is mortared to the gunite frame behind it, rests on supports on both sides, and is oriented so looking down from top you can see the layers in the stone. I have a salt water pool, and when the waterfall is on, water seeps into the mortar joint and drips out on the underside. Calcium stalactites form over time underneath, and I am sure the salt water is not great for the mortar joint itself, or the interior of the stone. I protect it from moisture in the winter with a cover so no water gets in and freezes, but I would also like to eliminate water from getting in in summer also. I have used 511 Impregnator for the last couple years, and it has helped, but the water is still getting in. Can anyone recommend a product that I can use on the entire top side of the waterfall that will essentially make the flagstone, mortar joints and rock beam waterproof without changing the color/sheen too much?