How do you monitor CO2 Levels?

[Jur4ik]

In Germany it must have been Dennerle

[plantbrain]

Originally Posted by Orlando

Not sure why folks still use that chart.

It can work if there's no interference.
DC's have a trade off.

I use pH and visual cues, calipers on the needle valves(Nupro makes some nice easy to reference handles) mostly myself.

I also am patient and slow to adjust the CO2. This prevents over gassing and stressing any fish. I add enough till I need no more.

Regards,
Tom Barr

[shayf]

Originally Posted by Supercoley1

Some people even think that a 1Ph drop is accurate. This is only if you have a specific KH. 30ppm will drop a different amount of Ph dependent on the KH within the tank so even this cannot be used.

I use a DC and a pH controller, but acctually, this one (for me) is the most accurate way to know my CO2 level, and I check it that way, once a month.

Assuming that water standing for 24 hours (at 1ATM and in room temperature) contains exactly 3ppm CO2, it will always be 1 degree pH difference to go to 30ppm CO2, no matter what is the KH.

There is a simple formula to calculate the exact CO2 level form the pH difference.
This formula is based on the KH/pH/CO2 formula -(CO2=3*KH*10^(7-pH)), and it goes like this:

Assuming X = Standing 24h water pH - Aquarium water pH
CO2=3*10^X

Example 1:
Standing 24h water pH = 6.83
Aquarium water pH = 5.76
X = 6.83-5.76 = 1.07
CO2 = 3*10^1.07 = 3*11.75 = 35.25ppm

Example 2:
Standing 24h water pH = 6.50
Aquarium water pH = 5.50
X = 6.50-5.50 = 1
CO2 = 3*10^1 = 3*10 = 30.00ppm

Example 3:
Standing 24h water pH = 6.50
Aquarium water pH = 6.10
X = 6.50-6.10 = 0.40
CO2 = 3*10^0.40 = 3*2.51 = 7.54ppm

Can someone please disprove it?