How do you monitor CO2 Levels?

[Joe Faria]

Originally Posted by waterfaller1

And what do the plants do? You are doing fine with english.

If you got enough/good light and nutrients available in water column, but no CO2 plants will show stunted growth... and algae will apear.

In the other hand having CO2 in excess(with limits of course) is no problem for plants, but can be dangerous, as you already know, for the fauna in your tank.
Having too much CO2 available can be a problem for plants as well, because in some cases,that will cause a lack of oxigen, resulting in stunted growth or very slow growth and algae striking again... plants use O2 when you turn off the tank lights. ( I almost forgot... beneficial bacteria uses O2 as well)

Confusing? Just a little bit... we just got to find the right balance for the tank needs.

Cheers,

Joe Faria

[Dan Pellegrini]

I-HEART-My-SMS122

I use a pH Controller w/ Solenoid on my Regulator + a Drop Checker. The Drop checker serves as a visual indication when the CO2 tank is empty, and a great verification that the controller is working. Even better, I don't bother calibrating my controller much, just make sure that where ever it is set is keeping the drop checker the right color.

If you do use a drop checker you REALLY need to use a kH Reference solution.

[mrkookm]

A correctly setup/placed DC in my tanks has been an invaluable tool thats has helped guide me in the right direction but now now that I have gained a little more experience with growing aquatic plants, nowadays I adjust as I see fit based on water flow, plant mass and overall plant health/response.

[BryceM]

I use a pH controller but am under no delusion that it is always accurate. It gets calibrated frequently and the probes get replaced at least once a year. I use RO and check frequently to make sure my KH is always steady. As a secondary check I watch for intensity of pearling. As long as I keep up on the ferts this is a good secondary check.

I bought a drop checker recently, but I haven't ever used it. Once I started looking into making a KH 4 reference solution it became evident that there are plenty of potential sources of error. The usefulness of the DC is really no better than the accuracy of the reference solution. You can either mix up a solution that is validated by your particular test kit or make up an empiric solution with a known mass of NaHCO3 and known volume of distilled water. The first method is no better than your particular test kit and the second implies a degree of accuracy in measurement that is beyond what most of us can do outside of a lab. NaHCO3 is hydrated to a variable (usually unknown) degree that makes it less than ideal for making a reference solution. For what I do, I think the pH controller is just as good, assuming a stable KH and frequent calibration of the unit.

[trenac]

When I first started in this hobby I used the KH/PH chart. Then once I became more aware of what the plants should look like, I started using the visual aspect. I now think I'm ready to step up to a drop checker.

[John N.]

Originally Posted by trenac

When I first started in this hobby I used the KH/PH chart. Then once I became more aware of what the plants should look like, I started using the visual aspect. I now think I'm ready to step up to a drop checker.

Shouldn't the progression be the other way around?

KH/PH chart - Drop Checker - Visual Ques (meaning you have an eye for plant health).

The drop checker popularized by Hoppy in Early 2007 really changed the face of CO2 monitoring in the past year.

-John N.

[plantbrain]

I use a CO2 dissolved gas analyzer.
It does not use pH or KH to measure and is about accurate in practical cases to 1ppm. 2000$ though but data logs etc.
So the measurement is entirely independent of any other interferences other than CO2 gas in solution.

You can make a Reference KH cell and use a membrane around a pH probe to DIY a far more accurate drop checker approach.
This has a lot better response time, but you need to get the membrane on good, replace it every 2 weeks or so, calibrate the pH probe etc.

This can get you close to the 2000$ unit.
But you need to do the DIY version.
Basically a DC but instead of Bromo Blue, you use a pH meter and no air gap, but a membrane.


Regards,
Tom Barr

[Orlando]

Where can I get one of these co2 dissolved gas analyzer's?

[plantbrain]

Originally Posted by Orlando

Where can I get one of these co2 dissolved gas analyzer's?

These guys sell them as well as YSI and other companies.

Co2 Analyser - Aquamerik - aquaculture & environnement

Regards,
Tom Barr

[Orlando]

Thanks Tom, that is one cool place with lots of expensive stuff

[Pny]

I've been using a DIY pH controller / monitor for som years now. It's nice to be able to get digital readouts like this...




But I think it still is important to watch both fish and plants to be on the safe side...

[George Farmer]

I use drop checker with 4dKH solution. I go for a mid-green, whatever that means...

Once I've figuered my CO2 bubble rate, it very rarely needs adjusting.

My CO2 comes on 3 hours previous to lighting, and off 1/2 before lights off.

[plantbrain]

So how do you measure very low levels of CO2 in a non CO2 planted tank and how would you explain the lack of algae in those systems?

BTW, folks all did non CO2 aquascaping long before you folks ever had electronic calculators, TV's, computers, or the net. Careful, not to be too CO2 bias in your outlook, view point and understanding of methods.

All this gibberish about Nature, natural looking, finding that balance and what not.........yet adding CO2 like this and amplifying growth rates 10-20X like industrial agriculture is far from "natural".

ADA does it too.
Then gives a nice poem about nature.
That's not a sustainable ecosystem and balanced.
Large massive water changes are not part of that philosophy either.

Using CO2 looks nice etc, it's horticulture/aquatic landscaping, but it's far far more related to industrial hydroponic pot growing or large scale agriculture than it is nature. Don't kid yourselves there.

How confident are we about CO2 and it's measure?
Not much really.
Even with a pH controller, you still are missing good readings from KH which can and do vary. Without knowing that data for the entire time the pH is on, then it really just says something about pH, not CO2.

Without really testing and looking at the easier methods, fish and plant observations appear to be the best. See a little algae start, bump the CO2 up a tad etc. But actually knowing what the CO2 ppm is at a certain point in time is tougher than many assume/it may seem.

Regards,
Tom Barr

[ColeMan]

Originally Posted by plantbrain

Using CO2 looks nice etc, it's horticulture/aquatic landscaping, but it's far far more related to industrial hydroponic pot growing or large scale agriculture than it is nature. Don't kid yourselves there.

I've always wondered if (or rather when) the DEA's going to knock down my door - I mean, ordering lights, fertilizers, CO2 equipment...sure seems sketchy to me! Has this ever happened to an aquarist? A case of mistaken identity?

[plantbrain]

Originally Posted by ColeMan

I've always wondered if (or rather when) the DEA's going to knock down my door - I mean, ordering lights, fertilizers, CO2 equipment...sure seems sketchy to me! Has this ever happened to an aquarist? A case of mistaken identity?

I think a few folks did, I know James P. had it happen back years ago.
He got pissed, but not at the cops, at the dang pesky nosey neighbor who thought the worst.

Still, something to ponder when folks claim what they do is "natural" with high CO2 injection and dosing etc.

It's ain't very natural at all.
It's just some presentation of a scene that they think is "natural".

However, there are a very few places where high CO2 does exist with plants etc. I show folks these radically different places that plants both exist. Plants grow in both high and low CO2 systems and everything in between.


Regards,
Tom Barr

[LauraLeeLLBP]

Looks like I'm the only "other" so I suppose I have to "specify" now... I don't. LOL

[defdac]

Other: Bubble counter. 1 bubble/sec is the sweet spot for my tank.

[Shadow]

I'm using drop checker, ph/kH table does not work with ADA aquasoil

[KDahlin]

I use a drop checker but I've found that, at least to my eye, it stays green over a wide range. I initially wanted to target 30 ppm and I did this by measuring the pH change of a small amount of tank water that has sat out in a paper cup for 24 hours compared to that inside the tank. A difference of 1 degree is supposed to equal 30 ppm. I raised the CO2 up 1.4 degrees chasing some algae, and the drop checker still looked green.

[Jdinh04]

I just mainly measure my ph and kh and use the comparassion chart to figure out what my CO2 is. I did however used a drop checker before, but somehow the solution leaked into my tank somehow and I had green water for weeks, although I may use it again after I try and fix it.