CO2 scrubber and side effects?

RDL · Feb 27, 2017

Hi, I am new to this forum so have hopefully posted by question in the right place.

I have been struggling to get my PH much above 8.1 during the day with lowes at night down to 7.78.

Given the low PH my LFS mentioned Co2 as a potential reason and said I could try a scrubber attached to my skimmer which I did. The great news is the night time low has stopped at 8.03 and the daytime high was 8.28 yesterday. Still a swing but not as low as it was for sure.

My question is around the alkalinity and calcium levels. I added the scrubber 3 days ago and when I tested last night, alk was at 9.24 dkh and Calc was 420 which is about normal for my mixed reef. When I tested tonight at the same time, alk was 6.78 dkh and calc was 290. I have not seen a change like this ever in the 2 years I have had my tank and the only change is the addition of the co2 scrubber which I am hoping is a good thing.

Testing was done 3 times tonight given the low readings using my Red Sea test kit.

I am dosing Seachem 1 and 2 and have been for about 6 months using a doser and have checked lines to make sure dosing is actually taking place and is. I dose calc during the day and alk at night and levels have been pretty steady for the most part.

I am hoping that someone here has had a similar experience or has an idea on what is happening and if it is to be expected with a scrubber.

Thanks in advance for any help.

3mm3 · Feb 27, 2017

RDL said:
Hi, I am new to this forum so have hopefully posted by question in the right place.

I have been struggling to get my PH much above 8.1 during the day with lowes at night down to 7.78.

Given the low PH my LFS mentioned Co2 as a potential reason and said I could try a scrubber attached to my skimmer which I did. The great news is the night time low has stopped at 8.03 and the daytime high was 8.28 yesterday. Still a swing but not as low as it was for sure.

My question is around the alkalinity and calcium levels. I added the scrubber 3 days ago and when I tested last night, alk was at 9.24 dkh and Calc was 420 which is about normal for my mixed reef. When I tested tonight at the same time, alk was 6.78 dkh and calc was 290. I have not seen a change like this ever in the 2 years I have had my tank and the only change is the addition of the co2 scrubber which I am hoping is a good thing.

Testing was done 3 times tonight given the low readings using my Red Sea test kit.

I am dosing Seachem 1 and 2 and have been for about 6 months using a doser and have checked lines to make sure dosing is actually taking place and is. I dose calc during the day and alk at night and levels have been pretty steady for the most part.

I am hoping that someone here has had a similar experience or has an idea on what is happening and if it is to be expected with a scrubber.

Thanks in advance for any help.

Do you have sps?
As ph increases above 8.2 coral have a much easier time growing. Ill look for a link. BRS tv has a video on this.

RDL · Feb 27, 2017

I do have SPS and all are growing very well (elk horn in particualr). My thought was to get the PH up because it should be and to see if I can get things to grow faster but didn't expect the alk and calc to drop like they have. Will have a look for the BRS link too.

3mm3 · Feb 27, 2017

RDL said:
I do have SPS and all are growing very well (elk horn in particualr). My thought was to get the PH up because it should be and to see if I can get things to grow faster but didn't expect the alk and calc to drop like they have. Will have a look for the BRS link too.

here is the link. start at around minute 5

More ph info.
http://www.reefkeeping.com/issues/2004-09/rhf/

RDL · Feb 27, 2017

Perfect! I see that they had the same thing happen to them. Going to take this the one step further and add a solenoid. Thx!

3mm3 · Feb 27, 2017

RDL said:
Perfect! I see that they had the same thing happen to them. Going to take this the one step further and add a solenoid. Thx!

I'm doing the same. I'm purchasing the solenoid and a controller. My ph is too high now. Went from 7.7ph-7.9 to a range of 8.3 to 8.44

RDL · Feb 28, 2017

Got my solenoid installed. Had to modify the amount of air it let in when open since its really designed for pressurized inputs but after mod works as intended.