Is there a method for testing dissolved O2 in our aquariums?

[Dom]

I ask this question because I am considering setting up a CO2 scrubber. But before I spend the money to add this equipment, I'd like to test and see if it is necessary.

Is there a method that we as hobbyists can use?

Thank you,
Dom

 

[ISpeakForTheSeas]

Yeah, there are ways to test oxygen levels:

For measuring oxygen:
https://www.chewy.com/salifert-aquarium-oxygen-test-kit/dp/379750https://www.hannainst.com/hi3810-dissolved-oxygen-test-kit.html

 

[Malum Argenteum]

How does testing dissolved O2 help decide whether to scrub CO2?

 

[Doctorgori]

How does testing dissolved O2 help decide whether to scrub CO2?

also, dissolved oxygen is variable with temperature, skimming, bio load/bio activity, et et
…sorta a moving variable, not sure what data collecting for O2 will yield…
There is also ORP which is a 3rd cousin to O2 …sorta, kind of

 

[Dom]

How does testing dissolved O2 help decide whether to scrub CO2?

Well... as I understand it, CO2 scrubbers are used to remove CO2. But you may not want to do it if you O2 levels are adequate.

So I thought, before I spend money on this accessory, test to see if it is necessary.

My understanding is that CO2 scrubbers make more oxygen available. I don't know.

Am I misunderstanding CO2 scrubbers?

 

[Doctorgori]

CO2 scrubbers remove CO2 which raises pH,
too much CO2 can suffocate you but not sure how that works in liquids

 

[Malum Argenteum]

My understanding is that CO2 scrubbers make more oxygen available.

I'm not sure how that would happen. CO2 scrubbers are used to remove some of the CO2 that can lower pH. I assume that's independent of the O2 carrying capacity of the water (unless the water is saturated with CO2, which isn't the case in any reef tank).

Is there some reason you think the tank is low on O2?

 

[Dom]

CO2 scrubbers remove CO2 which raises pH,
too much CO2 can suffocate you but not sure how that works in liquids

So people deploy CO2 scrubbers for the benefit of raising pH, not oxygen?

 

[Dom]

I'm not sure how that would happen. CO2 scrubbers are used to remove some of the CO2 that can lower pH. I assume that's independent of the O2 carrying capacity of the water (unless the water is saturated with CO2, which isn't the case in any reef tank).

Is there some reason you think the tank is low on O2?

Not at all. Actually, I would be fixing something that really isn't broken.

I misunderstood the function/purpose of CO2 scrubbers.

I thought there might be some benefit to my tank by installing one.

 

[Randy Holmes-Farley Verified Community Expert]

The issue with O2 and scrubbers only arises when using it in a pure recycling formate, eliminating the oxygenation capability of the skimmer.