CA Reactor plans

[kari]

Though perhaps it might be best to locate the probe in the bottom after the second chamber. Any advice on that?

Why not place the probe at the effluent outlet, like in your sump? That way you can use the same probe to measure tank ph and the reactor's.

My experience with Mag Drive pumps has been that I break 2 out of 3 pump covers before I'm done plumbing.