Thanks for your suggestions - I'll try and keep the TA at this lower number and allow a little higher PH and see how it goes.

I should've said that I don't actually run the aerator, I thought you asked so that in case I had one I could use it to adjust something.

The only "aearation" I can think of possibly happening is that I have 2 of the water returns pointing up toward the surface which causes some bubbling/movement...

Yes, I'm using the Taylor kit and got the reading by applying the method you described. And yes again, I will definitely post back a follow up when I nail down the problem.

Thanks a bunch!