Ready made drop checkers vs 4dkh solutions

Soggy

Junior Poster
Jun 27, 2007
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Peeps,

Does the ready made drop checker solution produce an equivalent 4dkH + pH tester when added to tank water?

will the reading be the same for the ready made ones if my tank water has really really high kH (18) vs using the DIY method?

thanks,
eric
 

Philosophos

Lifetime Charter Member
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Mar 12, 2009
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Not usually. The "ready made" stuff you get from places like aquaticmagic and such are just re-labeled bromothymol blue.

You wouldn't want to use tank water anyhow; it will have its own compounds floating around in the column that buffer pH. Use DI H2O instead.
 

nipat

Guru Class Expert
May 23, 2009
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If your tank's water is low in KH and PH and you use it in your DC,
your DC will probably be always green even if CO2 in your tank is low,
and vice versa if your water is high in KH and PH.

Try reading this http://www.njagc.net/articles/co2dropchecker.htm
And you will know why using tank water can be misleading about the amount
of CO2 in your tank.
 
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Soggy

Junior Poster
Jun 27, 2007
29
0
1
I ordered it just for the indicator gadget though.

I was also using the 4dkH way before this so i was wondering how it worked. Iguess the liquid that came with it is snake oil.
 

Left C

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Sep 26, 2005
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Burlington, NC
Drop checkers have been out for many years, but adding the 4 dKH carbonate based solution with its included bromothymol blue solution is rather new.

That is why your directions say to use aquarium water.

You can't use aquarium water even if it is 4 dKH either. There are more than just carbonates that add KH to the water than carbonates. Phosphates, other acids and bases add to the KH mix too. This invalidates the pH/KH/CO2 relationship. This relationship is only good is the water uses carbonates which is where the 4 dKH carbonate based solution comes in.

Read Chuck's explanation rather closely and will understand what he is saying about this relationship. http://csd.net/~cgadd/aqua/art_plant_co2chart.htm

VaughnH wrote a series of articles about them. Here is one: http://www.barrreport.com/showthrea...Indicators-Why-and-How?highlight=drop+checker