What’s the DKH in your effluent?

[Mike Lemming]

Still stable at 8.6. LFG!!!!

 

[JMetaxas]

I question any test kit that would measure that high of range.
Typical reef dkh is 6-12dkh. Do you really think your test kit would be accurate in the 30s dkh or even 20dkh?
I don’t even trust the PH measured inside the chamber since my probes are calibrated with 7 and 10 cal fluid.
Chasing numbers in a CaRX is stupid. Dial down the co2. Test the tank parameter. Dial it up slowly until the parameter is desired and stable. Check it periodically. Nothing is really set and forget.

I calibrate Ca+ Reactor pH probe with 4 and 7 calibration solutions. When measuring Alk of the effluent, I dilute with RO/DI water, typically 3:1 in order to bring it into range of the test kit. (I use Salfert)

 

[this is me]

I calibrate Ca+ Reactor pH probe with 4 and 7 calibration solutions. When measuring Alk of the effluent, I dilute with RO/DI water, typically 3:1 in order to bring it into range of the test kit. (I use Salfert)

Okay. That is good.
I still think chasing numbers in a carx is futile.
CARX doesn’t have to be this complicated. Set the effluent to a broken seam drip, adjust co2 and test the tank until you get a stable reading for 24-48hrs.