What's my real CO2 ?

reiverix

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Jan 29, 2005
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Water straight from tap - pH7
Tap water after 24 hours - pH7.4 (the water company adds CO2)

Tank water after CO2 injection - pH6.5
Tank water after 24 hours - pH6.9

My KH is 4 so I should have CO2 at around 34ppm. But my tank water has a lower pH than from the tap, I'm assuming because I have two largish pieces of driftwood. So how do I measure CO2, taking into account the fact that the wood is lowering my pH?
 

Spar

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Jun 5, 2005
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Re: What's my real CO2 ?

is the tanic release from the wood just lowering your pH or can you tell if a decrease of KH is occuring?
 

defdac

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Re: What's my real CO2 ?

reiverix said:
So how do I measure CO2, taking into account the fact that the wood is lowering my pH?
An easy way is to breath down a small cup of aquarium water for about 5 minutes with a straw (don't pass out ;) and measure the pH. The color you recieve from the pH-test is the color you should shoot for.

If the plants doesn't pearl with that pH, adjust you bubbel-rate up until fish gasps, then turn down just a notch.
 

reiverix

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Re: What's my real CO2 ?

I did not know that. Sounds like fun so I'll give it a go :) The reason I was asking is one of the wood pieces is quite new and some BBA started forming on it. My plants pearl fine but I can't help thinking my CO2 is lower than what seems. I killed off the BBA by spot treating it with Excel and it hasn't grown back but some staghorn is starting grow on my bolbitis.
 

reiverix

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Re: What's my real CO2 ?

I used a 5ml babies ear dropper from Wal-Mart. Slowly shoot it at the algae. All it takes is enough to make sure the BBA gets exposed so I was careful not to overdose. I limited myself to a max of 10ml a day in a 75g and after a few days the algae was red and dying. My ammano shrimp took a liking to it at this stage and polished it off.

I've also turned up my CO2 a notch and so far so good. I removed the staghorn but had to sacrifice a few of my older bolbitis leaves, which really sucks as some of them were quite big and took an age to grow.