Did you lower the T ? If you dont lower the T the gate valve will either not help at all or it will force the water level higher because of restriction. Lowering the T is the key to making the gate valve a useful addition. It serves the same purpose of an expansion coupler. Think of it this way ... with an expansion coupler, when you raise it up, the water level comes up in the skimmer, when you lower it the level goes down. All you are doing with an expansion coupler is raising and lowering the height of the output. A gate valve does the same thing. Closing it off raises the water level. But the only way to have control with it is to have a lower water level with it wide open. To do that, you must lower the output height ... the T. Then closing off the gate valve raises the level to wherever you want it, opening it up lowers the level.
Sorry if you already know this stuff, not trying to be condescending. Just trying to help make sure it works for you this time when you try it.
The shipped it assembled and it cracked really badly around where the pump attaches. So now I'm waiting on a response to me email on how to get a replacement.
