CO2 scrubber placement

[Fishfinder]

what would give the longest life for CO2 scrubber media. Having it recirculate air from the skimmer cup, or having it pull and scrub air from the outside? Would there be a noticeable difference in life between the 2?

 

[Diesel]

Co2 scrubbers are meant to scrub your indoor air.
If you can pull air from the outside through your skimmer you’ll get the same result or even better.

 

[Fishfinder]

Ok thanks for the info, I was under the impression that people were using scrubbers to achieve levels lower than outside air

 

[Randy Holmes-Farley Verified Community Expert]

There's no single answer for that question.

The media will last longer on outside air than on inside air with higher CO2 (assuming equal humidity), but we really do not know the CO2 level in skimmer outlet air. When people reports differences, it may be due to humidity rather than CO2, and humidity can be increased on outside air if you want.

Remember that if you use all recycled air for the smkimmer, the skimmer will not be usefully doing O2 exchange.

 

[Randy Holmes-Farley Verified Community Expert]

Co2 scrubbers are meant to scrub your indoor air.
If you can pull air from the outside through your skimmer you’ll get the same result or even better.

A scrubber on outside air can drop the CO2 in it lower than normal outside air, giving more pH raising effect.

 

[Fishfinder]

Thanks randy I did not consider that recirculating skimmer air would reduce o2 exchange

 

[Diesel]

A scrubber on outside air can drop the CO2 in it lower than normal outside air, giving more pH raising effect.

Of course Randy, but in most cases when you pull outside air through the skimmer the ph will stabilize to acceptable numbers.

 

[Randy Holmes-Farley Verified Community Expert]

Of course Randy, but in most cases when you pull outside air through the skimmer the ph will stabilize to acceptable numbers.

Often, yes. In some cases the tank top aeration is apparently defeating the outside air/skimmer effects.

 

[Fishfinder]

I would prefer to just recirculate my skimmer air. I just don't want to burn through media every few days. Especially when outside air will do the job for free.

I'm not looking forward to drilling a block wall. I guess I'll just have to pull the trigger and make a decision

 

[Diesel]

Often, yes. In some cases the tank top aeration is apparently defeating the outside air/skimmer effects.

You know as I know that in the early days we didn’t had that problem of a too low Ph.
Maybe cause they made the hobby affordable for most and cause of that compared to 20 years ago you have tons more hobbyist and will run into that event more often.
Or they made the homes more air tied due to Co2 build up.
Any way, I’ve been pulling air from the outside for over 10 years and I never have a problem even with a CaRx installed.

 

[Fishfinder]

@Diesel my daily ph swing will get down to 7.67-7.70

 

[Diesel]

Yes that’s bad and I feel your pain.
Outside air or scrub the heck out of the indoor air which is costing you some $$$$ over time.
Open top, enough water turn over, ventilate the sump area just to name a few.

 

[justingraham]

You know as I know that in the early days we didn’t had that problem of a too low Ph.
Maybe cause they made the hobby affordable for most and cause of that compared to 20 years ago you have tons more hobbyist and will run into that event more often.
Or they made the homes more air tied due to Co2 build up.
Any way, I’ve been pulling air from the outside for over 10 years and I never have a problem even with a CaRx installed.

I just had my house energy certified ie they came in and replaced everything with more efficient stuff and then they insulated my attic I also got Anderson windows
Before my ph was in the 8.2-8.0 range now I can’t get it over 8 with pulling air from outside and I just started scrubbing so hopefully it will get back where it was

Point of this post is I think houses are insulated way better that’s why you see more post about this

 

[Diesel]

I just had my house energy certified ie they came in and replaced everything with more efficient stuff and then they insulated my attic I also got Anderson windows
Before my ph was in the 8.2-8.0 range now I can’t get it over 8 with pulling air from outside and I just started scrubbing so hopefully it will get back where it was

Point of this post is I think houses are insulated way better that’s why you see more post about this

Maybe so.
I’m a builder and many times when ppl remodel the get a over rated AC which results in a overdraft of air, double insulation which cut of fresh air flow.
I have seen it all and so the compensate on extra equipment on the tank.
I get only 6 hours of fresh air in as I run my skimmer only 6 hrs during the night.
Just cause many skimmers are overrated for the system they run on.
Yet the Ph is 8.09 on the low to 8.22 in the high.
Just find the sweet spot

 

[Randy Holmes-Farley Verified Community Expert]

I just had my house energy certified ie they came in and replaced everything with more efficient stuff and then they insulated my attic I also got Anderson windows
Before my ph was in the 8.2-8.0 range now I can’t get it over 8 with pulling air from outside and I just started scrubbing so hopefully it will get back where it was

Point of this post is I think houses are insulated way better that’s why you see more post about this

My pH dropped substantially when I got new storm windows.

 

[Diesel]

My pH dropped substantially when I got new storm windows.

Hehehe.......... your a scientist..... fix it Randy

Inject pure oxygen into the skimmer or do I open up a can of worms here??

 

[Clownfishy]

I am getting 4 weeks out of my Soda Lime granules and my scrubber is setup as shown in picture below. Here is the thread that shows how I maintain my ph above 8.30 using a combination of the scrubber and dosing alk and also kalkwasswer -
https://www.reef2reef.com/threads/my-experience-raising-ph.394826/
I guess we should also take into consideration how much air our skimmers are drawing which contribute to the length of time the granules will last.

 

[Randy Holmes-Farley Verified Community Expert]

Hehehe.......... your a scientist..... fix it Randy

Inject pure oxygen into the skimmer or do I open up a can of worms here??

O2 isn't the answer, but just normal air without CO2. If you really tried to drive out CO2 with pure O2, the O2 level would get too high. Like 4-5x normal.

FWIW, my pH was always high (8.35 to 8.55) due to limewater and very fresh air in a leaky old home, but the lowering with new storm windows was no concern.

 

[Diesel]

O2 isn't the answer, but just normal air without CO2. If you really tried to drive out CO2 with pure O2, the O2 level would get too high. Like 4-5x normal.

FWIW, my pH was always high (8.35 to 8.55) due to limewater and very fresh air in a leaky old home, but the lowering with new storm windows was no concern.

That would work.
So pressurized air in a 60/40 mix could work?
I’m asking your take of in as a scientist.

 

[Want2BS8ed]

Remember that if you use all recycled air for the smkimmer, the skimmer will not be usefully doing O2 exchange.

Randy, I would still like to understand the basis for your opinion on this. We have discussed the end state of the scrubbing media used for CO2 removal, but what exactly is the chemical reaction that takes place? CO2 goes in, but what comes out of the scrubber and why does additional moisture (assumed to be H2O) extend the life of media?

Not trying to be difficult, but truly want to understand.

Typing out loud (always dangerous) regarding O2, in theory, if a perfectly closed system were created and all available O2 were to react with organics in the water column and be depleted, wouldn't the skimmer itself stop working - i.e. blowing bubbles, but not stripping organics?