CO2 and O2 test kits

[TNfish]

Hello,

What do you recommend for testing your planted tanks for CO2? I have seen referenes to LaMotte. Also, Tetra has an O2 test kit. Do you typically measure both, or just one? How often? What is the range (in ppm) that should be strived for?

Help is appreciated.

Tom

 

[rkilling1]

Tom, I can't speak for everyone, I do not measure O2. As long as you have a heathly aquarium there realily isn't a need for it. Your fish will let you know if there was a problem, sometimes maybe too late. As long as there is water movement and surface agitation, that all that is needed for O2 exchange. In the planted aquarium the O2 is added by the plants.

As far as CO2 kits, I'll have to have someone else answer that one as I do not use one. I do know that some like to constantly monitor thier levels inside thier tanks by using a glass 'kit' , if you will, that is filled with a buffer that changes color based on pH. I monitor my levels by using KH and pH.

 

[rich311k]

I don't think anyone test for O2. As long as the fish are not at the top gasping they are fine. You want to strive for a CO2 level above 30ppm in a high light situation. Consistent is very important if you run less the 30ppm. You can get CO2 levels by using your KH and PH tests. Red Sea makes a CO2 test which I have read is fairly good. How much light do you have and what size tank?

 

[newfound77951]

From experience I would say that any aquarium-hobby-grade O2 test would not be even remotely accurate....O2 is complicated to measure in a lab setting!

I have the Red Sea Co2 kit and don't really trust it. It gives me different readings every time I use it. I think calculating CO2 from KH and pH is probably the best way to go for the average hobbyist....CO2 is also complicated to measure in the lab (ask me how I know this.....)

 

[rkilling1]

O2 is complicated to measure in a lab setting!

Not so. Do it all the time on numerous sample points. ampules can be puchased and can give accurate results to the average Joe.

http://www.chemetrics.com/vacuette.html

(I deleted a paragraph i had writen that I thought may have been taken wrong and has nothing to do with the OP.)

(ask me how I know this.....)

OK, how.

looking at chemetrics websites, I see they have a CO2 test kit for 28.00.

http://www.chemetrics.com/instructions/i1910.pdf

may have to try that out. we use the CHEMets all the time for low level O2 and so does the rest of the Nuclear industry and the United States Navy. I will just have to see how accurate my CO2 really is.

 

[newfound77951]

Interesting....they don't list the accuracy of the test, however. I just think that for most hobby grade, hand-measured test kits the accuracy, particularly at the low end of the scale, isn't enough. But I'm always interested in better mousetraps.

How....I run nutrient analysis by segmented flow auto analysis (colorimetric), O2 using Winkler titration and spectrophotometry, and CO2 (DIC) using acid digestion and IR.

Maybe I'm just too used to high accuracy, but I view most available test kits with a skeptical eye. They did list MDLs (Minimum Detection limits) on some of the tests.

OK, I just realized that we're talking apples and oranges here.....no use comparing color matching tests to instruments that give numerical output.....sorry about all the confusion. On the original point, most folks here use pH and KH to test CO2, and dont worry about O2.

 

[TNfish]

Thanks for the replies. I will use the KH and pH to determine CO2.

BTW: Tank is 125 gal. with 192 Watts light, 6700K

 

[Blackwood]

BTW: Tank is 125 gal. with 192 Watts light, 6700K

I use the same setup in my tank. It comes out to about 1.5wpg. Is this considered, low, or medium lighted tank? I know it's not high.

I have actually 4 96w bulbs, but only keep 2 of them on because I was having big algae problems with all 4 on at 3wpg.

 

[JDogg]

BTW: Tank is 125 gal. with 192 Watts light, 6700K

I use the same setup in my tank. It comes out to about 1.5wpg. Is this considered, low, or medium lighted tank? I know it's not high.

I have actually 4 96w bulbs, but only keep 2 of them on because I was having big algae problems with all 4 on at 3wpg.

1.5 wpg is considered in the low range, for the most part CO2 does not become "necessary" until you start getting over 2 wpg or so if you are running 3 wpg and do not have co2 (don't know if you do or not) then i can see why you might be having algae problems...

 

[Purrbox]

Actually it would probably be considered Medium Low Light. It's enough light that you will be able to grow a greater variety of plants than if you just had Low Light (ie 1WPG).

 

[JDogg]

Actually it would probably be considered Medium Low Light. It's enough light that you will be able to grow a greater variety of plants than if you just had Low Light (ie 1WPG).

medium low is in the "low range" kind of...

 

[TNfish]

I use the same setup in my tank. It comes out to about 1.5wpg

Actually, if you have a 125 gal. tank and use internal measurements, plus take into account substrate, plants, equipment (heater, overflow box/other filtration, etc.), you should have close to 100 gallons of water, i.e. 1.9 wpg. 4x96 becomes 3.8 wpg. Have you considered running all four only parts of the day?