This heavy duty grate is the foundation for creating a pond-less or disappearing water feature.
Grates are 2 feet x 4 feet by 2-5/8" thick and are made of high-density polyethylene (HDPE). The openings in the grate are approximately 1 x 1-1/4 inches.
We have used this grate with 8" x 16" concrete block spaced as illustrated. In this application we have added as much as 400 lb of stone and still be able to walk on it. This is presented as a guide only. Your own application may or may not require additional support.
There are 2 main ways to use the grates as illustrated at left. For shallow basins for disappearing fountains cinder blocks are used.
For deeper systems including disappearing waterfalls or rain harvesting tanks the grates connect together using 2" PVC pipe to create a support structure. This method requires a top and bottom grate.