Hi New;

Some years ago, I decided that this would pretty much be a pool only forum, rather than a pool and spa forum.

There are a bunch of reasons for this, but the main one was that, while it's possible to keep a pool sanitary within the limits of what people are willing to do, it doesn't seem possible to keep a spa sanitary, without requiring more maintenance than most people will do.

In other words, pools are broken and I can help you fix them, but spas are also broken and I can NOT help you fix them!

I've never felt this was the wrong decision. However, this line has been blurred from time to time by pools with attached spas, like yours. So I'm leaving your thread up.

That said, you have a piping, valving & control problem. They are very hard to troubleshoot well without accurate information. In this case, that means a set of digital photos of the piping, filters, and pumps and an explanation of how the piping works (or should work) as you understand it. Send them to poolforum AT gmail DOT com, and I'll post them.

Good luck