KH Buffer Question

[garth7]

Hello,

I have had my tank set up for well over a year and a half. I have been tinkering around with DIY C02 in coke bottles and a DIY CO2 reactor.

From what I had read in my KH test kit and some things on the net, I found that you can use the KH readings and PH results to measure the amount or get an estimated amount of CO2 in the water.

So, the other night I started testing before adding my new C02 diffuser. I had a 40 ppm KH buffer and a 7.6 ph. I added the diffuser and then next day my ph went down to 7.4. The next day it was down to 7.2. I, out of curiosity, measured my KH again and found that this had dropped as well. It was now at 20 ppm.

I was under the assumption (and we all know what assuming does) that the KH would stay the same. Is this not true? Or, am I just on the wrong track measuring my CO2 levels.? Please help....

Doug

 

[rkilling1]

The 'off the shelf' kinda kits, assuming that's what you have, are not that accurate. You are talking about a difference of 1 drop here.

If you want a MUCH better method to monitor your CO2, look into purchasing a drop checker and certified reference solution. Look at the stickies in this forum.

 

[travis simonson]

I'm with rkilling, it is not a good idea to place too much faith in the accuracy of most common liquid test kits. And your assumption is correct, KH should not decrease when supplementing with CO2.