Affect Of Bogwood On Co2 Calculation...

[Squid]

I have just started adding Co2 into my tank and so have been measuring the Co2 by testing the KH and the PH. I have also been reading different discussions about how the readings can be affected in this dicussion between a couple of people.

This got me thinking about other things that might affect the PH, such as Bogwood, which people say can reduce the PH of the water. Could somebody tell me the affect the this will have on the readings, or will the bogwood also affect the KH and so result in the Co2 readings remaining accurate..?

Cheers
Squid

 

[Aeropars]

Theres far to much guess work in this calculation and variables we cannot measure due to toxins in the water. Get a drop checker and make a KH4 solution as a refence point. Theres a thread on here about it.

Lee

 

[Squid]

Theres far to much guess work in this calculation and variables we cannot measure due to toxins in the water. Get a drop checker and make a KH4 solution as a refence point. Theres a thread on here about it.

Lee

This question is a little more generic.. I'm not after an exact calculation. Just an idea as to whether Bogwood would make any readings innacurate, or would have an affect on both PH and KH, and so result in the readings being kept in line and giving me relatively accurate Co2 readings.

Appreciate the comment though, and i will have a look at the thread you mentioned too.. thanks..

Squid

 

[JamesC]

Will bogwood affect the results? In my experience yes it does quite a bit. There are other factors as well. pH is fairly straight forward to measure and you can get quite an accurate reading using a calibrated pH meter but there may be more acids than just carbonic acid (from CO2) in the water. Weak acids like acetic acid and phosphates seem to cause problems. Also there can be problems measuring the KH (or alkalinity) accurately. Rather than try to explain it I'll post a link for you - http/www.advancedaquarist.com/issues/feb2002/chemistry.htm. It mainly talks about marine tanks but is also relevant for freshwater setups.

James

 

[Squid]

Will bogwood affect the results? In my experience yes it does quite a bit. There are other factors as well. pH is fairly straight forward to measure and you can get quite an accurate reading using a calibrated pH meter but there may be more acids than just carbonic acid (from CO2) in the water. Weak acids like acetic acid and phosphates seem to cause problems. Also there can be problems measuring the KH (or alkalinity) accurately. Rather than try to explain it I'll post a link for you - http/www.advancedaquarist.com/issues/feb2002/chemistry.htm. It mainly talks about marine tanks but is also relevant for freshwater setups.

James

So.. if i measured the PH of my tapwater, then measure the PH of the tank water prior to CO2, then work out the difference CO2 makes to my ph, and subtract that difference from my tapwater reading (rather than the using the tank PH) and used that for the CO2 chart, would that make it more accurate..

Squid

 

[JamesC]

I see where you are coming from but the answer is no. The more tests you do to obtain a result the more you add to the inaccuracy of the final result. You are making too many presumptions about the CO2 levels in the tap water and tank water being the same. Only takes a small difference to be out by quite a bit in the final result.

The drop checker method is the best yet that is relatively cheap and easy to do. The one point drop in pH method also works well but this is also presuming that the standing water has 3ppm CO2 in it.

I never really worried too much what my levels are and for a long time I never really knew. The KH/pH chart method kept telling me I had more than 100ppm. I've come to learn if my levels are OK now by knowing how the fish and plants react. I have started to use the drop checker method as it is so easy, but still rely on the fish and plants to tell me if anything is wrong.

James