At High Desert Koi Ponds we try and show our customer’s different examples of how ponds can be built. This pond is dry stacked block, with cells filled with concrete. It’s a perfect rectangle so we used one of our custom made drop in liners. This pond has one Koi Toilet Bottom Drain feeding a pair of our sand/gravel filters. It dosn’t have a skimmer, just an overflow for the “Flow Through” well water system we use on all out “store tanks and/or ponds.