Is a second PH monitor really needed?

[dooleyb]

For you folks that are running calcium reactors:

Do you have a PH monitor/controller to monitor the PH from the calcium reactor and inject CO2 and another PH monitor to monitor the PH in the reef tank? I use this setup in both my reef tanks but have heard of folks using only one PH monitor/controller. Can someone explain how they monitor the tank's PH and the PH from the reactor with only one monitor/controller.

Your feedback is appreciated.

[melev]

I have an AquaController II hooked up to my reef, and it constantly measures the pH of the tank.

I have a Milwaukee pH Controller that turns the CO2 on and off to my Calcium reactor based on the pH level of the effluent coming out of it. Using the pH Controller, I don't have to fiddle around with the reactor. The only thing I do each day is look at it to make sure it is running as it should, and I never have to worry about alkalinity or calcium levels in my tank. It is a great product for those that want to set it and forget it.

You can see the Milwaukee pH Controller in this picture. It is the bright green device.
http://www.melevsreef.com/pics/07/10/ph_controller_plugs1.jpg

The effluent is pouring (not dripping) out of the tubing into the acrylic container, where the Milwaukee pH probe can measure it at all times. The effluent then pours out a small hole in the front and trickles into the sump below.
http://www.melevsreef.com/pics/07/10/effluent_cup1.jpg

[SDguy]

I always wanted a second one. But honestly, after a year, I decided I don't need one. I keep the one I have in the ca reactor effluent. The AC Jr. is set to emergency shut off the solenoid if it gets too low. Otherwise, it's open 24/7.

Once in a while I check the tank pH. It's always the same....