Common sizes of polyethylene tanks include 50, 100, 150, 320 and 610 gallons, but can range in size from 30 to 1500 gallons. People use these tanks for koi ponds, aquaculture or watering livestock. The tanks may be round or oval shaped. Some large tanks include drain plugs for easy draining.
Other uses for polyethylene tanks include providing an indoor habitat for aquatic pets, storing minnows at tackle shops, raised garden beds or as a baptismal font for baptisms at cowboy churches. People can use larger sized tanks as swimming pools, and can enhance the pools by adding re-circulating pumps, waterfalls and filters. They can drain the water with a hose and direct the water to plants or gardens.
People can also use stock tanks to create water features in their yards or gardens. They place a stock tank in their desired location and add mounds of soil for growing plants. They then fill the trough with water and add water lilies or other aquatic plants, and goldfish. The combination of sun, plants and fish naturally de-chlorinates the water.
Other people use polyethylene stock tanks to collect rainwater from roof run-off and gutters where the practice is legal. Rainwater is naturally soft, so they can use it in gardens or wash houses.