Slide or Gate Valves are basically the durable guillotine valves which can stop water flow with the push of a handle. Much easier and better than ball valves because a ball value can easily be scratched causing leakage due to the particulate in pond water.
Most gate or slide values are manufactured from ABS plastic. This is similar to PVC, but not identical. It is imperative that the only glue that is used, after using clear primer, is clear multi-purpose (PVC-ABS-CPVC) glue. If only PVC glue is used to connect a PVC pipe to an ABS value, it will leak.
Gate or Slide valves are used in several spaces in a good filtration system because they can isolate a filter component. For example, if you wanted to isolate a Vortex chamber for cleaning or other maintenence, you could gate valve both sides of it and conserve the water in the other chambers. If you want to perform filtration services and you don't want the pond draining out while you do it, a gate valve works there, too!
Finally, if you want to create a useful bypass system for your UV (for example in winter) you can engineer the bypass and then use a single gate valve to execute the water bypass.
These valves are sold based on the size PVC pipe they accomodate. For example, the 2 inch Slide valve will take a 2" stick PVC and uses the same glue as PVC. After all these valves are made of PVC. The 3" slide valve takes 3" PVC and so on.
Value Handles manufactured from the highest quality stainless steel.