Due to excessive CO2 in my house, probably a result of it being newly built and energy efficient, the pH in my tank was lower than I would like. It would get down to about 7.6 at night and only up to 7.9 at its peak even while dosing kalk in my ATO.

To fix this I simply ran tubing from a window i kept cracked open to the venturi on my skimmer. This allowed fresh air to be injected into the water instead of the mixture of air and CO2 that is in my house. The result was great, 8.2 at night, 8.6 at the peak. But the downside was having to walk over 25 feet of tubing going through my hallway. So I found out that soda lime absorbs CO2, and is used in all sorts of lab and hospital applications for doing just that. Perfect.

First I needed a way to contain the media and then hook it up to my skimmer venturi. Scrounging around my garage I have this container that holds various sizes of clamps



I cut a hole and put in the correct size barb fitting for my venturi airline





On the other end I just poked a bunch of holes in it



Then I put a filter bag over one end to help filter out any dust that might get sucked in





Back together again



And running. Don't mind the clear skimmate, it overflowed while i was working with the airline.