Hey Ricky, sorry I posted those questions before going into the office. The other Brad has about the same answers I was going to have.
I am not sure how long you have had the CR but when I set mine up I first set the bubble counter to roughly 35 per min as a base line, slowed the effluent to one Qt per Hr.
My target was an effluent ph of 6.5 and the KH should be around 35-40.
I ran a marine pinpoint PH controller and had the high set at 6.6 and the low at 6.4, so at 6.6 it kicked n the solenoid and at 6.5 it turned it off. The 6.5 was "the center value" or the off target.
It may not be correct but perhaps your effluent's PH is to high-you want to shoot for 6.5.
At those set points it kept ( I say kept because I just bought a reef keeper elite, and now I am starting all over, with the addition of a kalk reactor running off the RKE) my KH at 10.8 and calcium at 440-rock solid for about 3 months-it truly was set it and forget, so I cant relate to the "constant tweaking" at least wit the controller I used.-which is now for sale-LOL
The only reason I switched to the RKE was I wanted to incorporate the Kalk reactor and with the new RKE so I have one controller to run everything. My ph never got above 8.13 during the day and dropped to 7.85-7.90 at night-not major but I wanted more consistency, plus I want to shoot for at least 450-500 for my Ca, and keep the KH around 11 bur the PH stay around 8.2-8.3-My goal anyhow-
Sorry for the long message-in short test that effluent PH maybe its not melting the aragonite fast enough-or while I'm on that what media are you using. Myself I use ARM by Carib Sea.
Good luck!