View Full Version : PH control in Tank vs Ca Reactor?

04/04/2009, 08:58 AM
I'm new to PH controllers and need some help. I have my AC3 "monitoring" the PH in my tank and in my Ca reactor. I currently am having it "control" the Co2 based on the Ca reactor reading somewhere between 6.4 and 6.8.

This is not helping to stabilize the Ph in my tank (which I would like around 8.3- 8.4 but runs lower) and from my reading many people go by the PH in their tank to set up the Aquacontroller parameters to control the Co2. I don't understand how this works.

I would really appreciate any advice!

04/04/2009, 10:13 AM
What is your tank PH; you don't "control" tank PH, and most tanks will not hold 8.3-8.4 PH due to any number of issues. I'd suggest to 1st determine if you have a PH problem and go from there.

What is your alkalinity and have you performed an aeration test (to check internal C02 concentration).

See this article, it might help...


04/04/2009, 01:07 PM
Ken, I'm new to Ca reactors and Aquacontrollers so trying to educate myself (it is a challege). It is my understanding that you should keep PH in your Ca reacotr at a certain level to dissolve aragonite without turning it in to mush. The PH in my reactor is good. The PH in my tank is too low. I realize there are a number of factors. My Ca has been around 380-400 and alkalinity about 8. I have not measured the aeration but will test it later this evening. I had read that most people shoot for having the PH in a reef tank around 8.3-8.4 for optimal coral growth. I understand that this may not be necessary but my PH has been as low as 7.8 at times which worried me. Thank you for forwarding the excellent article.

04/04/2009, 01:19 PM
pH is too low because of the reactor most likely, have you thought of dripping kalk to counteract the low pH and at the same time help you elevate the tank's pH and maintain calcium and alk levels?

I dont see 7.8 being a problem if thats what it was as long as you keep your alk within range

04/04/2009, 03:33 PM
Yes I am considering dripping kalk although I was hoping the Ca reactor would be sufficient. I have a lot of sps frags but they are all still fairly small. For some reason my ph was too low even before te Ca reactor. I appreciate the info.

04/04/2009, 03:53 PM
I have a friend with a 180g with a bunch of SPS and quit using a calcium reactor. He decided to dose two-part using 2 peristaltic pumps. He said he likes it a lot better, seems easier and cheaper to me and you have the option of using ALK that can either raise or lower your pH

04/04/2009, 05:17 PM
This article should help: