CO2: KH/PH Chart

[Delapool]

I came across this article where the CO2 concentration can be referenced if ph and kh is known. I was wondering if this can be used as a rough guide to CO2 level in a tank? I don't inject CO2 but was trying to understand this area a bit more.


CO2: KH/PH Chart

 

[Kushgodrex]

Idk about that but you can get a drop checker, it's really easy to check and could last a lifetime. You only need to replace the liquid inside it. This is the one I have
CAL AQUA Preal Drop Checker | Green Leaf Aquariums

 

[mrvincent]

CO2 is very hard to mesure from PH/KH. most PH test are not 0.1 accure, and KH tests 2.

The best way to know your CO2 levels, is to buy a CO2 drop checker with a 4dKH solution and put some bromotymol blue in there.

In a 4dKH solution, the PH in the drop checker will change depending on CO2 in the tank, and will give you an accurante color.

Blue = poor CO2
Green = good CO2
yellow green = high CO2
yellow = too much
red = (You should see most of your live animals floating at this point)

I use it at home and it's very accurate. From my experience, invest in a 4dKH solution (eBay), making it at home with baking soda is not so good, the solution is dropping a bit in dKH overtime and KH test kit are not so much accurate.

 

[Delapool]

Many, many thanks for the info - will check out.

 

[aqua_chem]

It can give you a rough estimate. The calculations are made assuming that there are not other acids/bases in the water; essentially that it's just water, bicarb, and CO2 (and intermediates). That's a pretty optimistic equation, especially when you've got non-inert substrate, driftwood, high bioload, etc.... so you can run astray of the ideal circumstances pretty easily. Add this to the low accuracy of the tests involved and you've got a very rough estimate of CO2.