This is a prep job I did for a project to be tiled with Oceanside Glass. Slightly over killed, but adequate to me. The walls of the fountain are concrete block and the floor is floated with dry pack cement.
First I ground down all joints on the block wall with a grinder and tile blade to smooth out the mortar. Second, I skim coated the block wall with Laticrete 254 Platinum. I let that layer dry and went over it with a scraper to knock down trowel ridges. I then added another layer of Lat 254. Let that dry and scraped, followed by the same steps one more time. Each step successively smoothing the wall until my six foot straightedge showed less than 1/16" variance in plane.
Next I floated the fountain floor in deck mud to create a perfectly flat substrate. There is no need for pitch with anti-vortex drains and a pump system. After cutting the stub pipes at the proper elevations and capping with the appropriate fittings I then skim coated the dry pack once with Lat 254 to make a nice smooth surface.
