Measuring CO2 and Safety for Fish
Tropical Fish

Tropical Fish Keeping - Aquarium fish care and resources » Freshwater Fish and Aquariums » Beginner Freshwater Aquarium » Beginner Planted Aquarium » Measuring CO2 and Safety for Fish

Measuring CO2 and Safety for Fish

This is a discussion on Measuring CO2 and Safety for Fish within the Beginner Planted Aquarium forums, part of the Beginner Freshwater Aquarium category; --> Forgive me for being lazy; however, I'm looking for a low tech way to measure CO2 levels and would like to know the safe ...

Like Tree4Likes
  • 2 Post By armymp327
  • 1 Post By Byron
  • 1 Post By Quantum

Reply
LinkBack Thread Tools vBmenu Seperating Image Search this Thread vBmenu Seperating Image
Measuring CO2 and Safety for Fish
Old 05-01-2013, 09:52 PM   #1
 
fish monger's Avatar
 
Measuring CO2 and Safety for Fish

Forgive me for being lazy; however, I'm looking for a low tech way to measure CO2 levels and would like to know the safe range insofar as fish are concerned. Currently, I'm running a little DIY CO2 setup with a betta being the only resident. The plants are beautiful and the betta isn't bothered as he breathes from the surface anyway. Any info would be appreciated. I'd like to try the DIY CO2 in a couple of other tanks to see the reaction of the plants but, I don't want to harm the fish.
fish monger is offline   Reply With Quote
Old 05-01-2013, 10:16 PM   #2
 
a drop checker would be the best way, you can find these cheap on Ebay

though there is also the PH/KH method, you test you KH then your PH match it up to the chart below on you will have your rough Co2 concentration.

safe range would be anything below 30ppm i believe, though the chart says 25 ppm.
Attached Images
File Type: gif ph_kh_co2.gif (24.0 KB, 52 views)
Mikaila31 and fish monger like this.
armymp327 is offline   Reply With Quote
The Following 2 Users Say Thank You to armymp327 For This Useful Post:
ColoradoUtah (05-01-2013), fish monger (05-01-2013)
Old 05-01-2013, 10:29 PM   #3
 
MoneyMitch's Avatar
 
mika would be the one to ask about this >.>
MoneyMitch is offline   Reply With Quote
The Following User Says Thank You to MoneyMitch For This Useful Post:
fish monger (05-02-2013)
Old 05-02-2013, 12:14 PM   #4
 
Byron's Avatar
 
I'll leave this for the CO2 experts to answer, other than to say that the CO2 should only run during daylight, meaning when the tank light is on. It is running CO2 at night that can be very dangerous.
fish monger likes this.
Byron is offline   Reply With Quote
The Following User Says Thank You to Byron For This Useful Post:
fish monger (05-02-2013)
Old 05-03-2013, 03:09 PM   #5
 
MoneyMitch's Avatar
 
Quote:
Originally Posted by Byron View Post
I'll leave this for the CO2 experts to answer, other than to say that the CO2 should only run during daylight, meaning when the tank light is on. It is running CO2 at night that can be very dangerous.
which also includes diy setups too! (yeast doesn't turn off at night)
MoneyMitch is offline   Reply With Quote
Old 05-03-2013, 03:24 PM   #6
 
Quote:
Originally Posted by armymp327 View Post
a drop checker would be the best way, you can find these cheap on Ebay

though there is also the PH/KH method, you test you KH then your PH match it up to the chart below on you will have your rough Co2 concentration.

safe range would be anything below 30ppm i believe, though the chart says 25 ppm.
geee my ph of 8.4-8.8 and kh of 4 degrees means ther eisn't a whole lot of co2 in there
beaslbob is offline   Reply With Quote
Old 05-03-2013, 03:56 PM   #7
BWG
 
Quote:
Originally Posted by MoneyMitch View Post
which also includes diy setups too! (yeast doesn't turn off at night)
I think that a lot of people that use DIY also run a bubbler at night because of that.
BWG is offline   Reply With Quote
Old 05-03-2013, 04:42 PM   #8
 
Armymp327 hit it dead on. Best get a drop checker.
Mikaila31 is offline   Reply With Quote
Old 05-05-2013, 08:57 AM   #9
 
Armymp327
Could you post the site for the chart so that I might print it out or can we place this in the reference section for future use? This seems like something that ought to be more widely available.
ColoradoUtah is offline   Reply With Quote
Old 05-05-2013, 11:25 AM   #10
 
Quantum's Avatar
 
what that chart shows is the ratio of the carbonate species vs pH

I think better understood when represented this way:

image016.jpg

CO2 in water forms carbonic acid (H2CO3), so comparing the chart and graph CO2 = H2CO3, and since KH = HCO3- + CO3--, think of the pink and green lines as only one (without the dip at around pH 10, since this just illustrates the relative amounts of carbonate and bicarbonate and combined they equal 100% of the total) and call it KH

so basically all that being shown is that a little above pH 6, 50% of the carbonate species total is H2CO3 and 50% KH, above which KH predominates and is exclusive above about pH 8.3, below pH 6 H2CO3 predominates and is exclusive below approx pH 4

so for beaslbob, yes there is no CO2/H2CO3 at those higher pHs, all the carbonate species exist as KH

but aquaria are open systems exposed to the atmosphere and this affects all of this as the system tries to reach equilibrium, including the exchange of atmospheric and dissolved CO2 which means the levels are not fixed - the graph shows relative, not absolute amounts

I'm assuming 'dangerous' levels of CO2 are greater than the saturation level, so the only way for it to remain dangerous is to introduce CO2 at a rate equal to or greater than the rate it can leave the air/water interface or be consumed by plants
Byron likes this.
Quantum is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Measuring Low KH equatics Beginner Planted Aquarium 2 07-07-2012 11:45 AM
Fish food safety alidawn15 Freshwater and Tropical Fish 3 07-09-2011 12:03 AM
Question about measuring fish Amethyst123 Freshwater and Tropical Fish 1 04-15-2011 04:06 AM
Automatic Instrument For Measuring Water Quality, for fish owners TimH DIY Aquarium 10 06-16-2009 01:00 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search



All times are GMT -5. The time now is 08:27 PM.