*PLUMBERSSTOCK EXPERT* responded:
Hello! We value your interest in our Little Giant 509081 WCR-9SP Wastewater system 20"X30". According to Little Giant, it will come down to how many gallons per minute you need and the diameter of the pipe. Also, if you already know the length of the pipe that will be needed. We hope this helps. If you're interested in purchasing the Little Giant 509081, feel free to click "Add to Cart", enter your zip code and you're ready to go. Thank you for visiting PlumbersStock.com. Happy shopping!