How do you guys manage co2?

[Gilles]

It is common practice here in the Netherlands to use a PH controller which monitors the PH value in the aquarium. In the US and other countries it is common practice to just bubble away if i may say so.

This thread is not to discuss what is best, but more what did you do to overcome some of the questions i have.

(1) Using a PH controller:
pro: Fish can't be gassed
con: CO2 is not on 24/7, so deficiency can occur even though not in all areas of the tank.
con: PH value measured by controller is affected by other factors and buffers

(2) Using a drop checker:
pro: Stable supply of CO2, 24/7 or when the lights are on
con: The fish can be gassed if the bubble rate is to high
con: How do you cope after trimming? There is less CO2 demand so Fish are more likely to be gassed.

Well obviously i am thinking of "going bubble" and not use my PH controller anymore. How did you guys handle the last 2 cons of method 2?

 

[nipat]

I used DC, to get the range of suitable bubble rate that made it green.
I also observed my Angelfish, if it's still interested in food. The bubble rate was OK.
Later I removed the DC and used the fish alone.
My bubble rate was 120-130 BPM (20 gallon tank).


But now the bubble rate is just 37 BPM. Well, I just read Tom's posts here and
there and see that his bubble rate is very low.
http://aquariacentral.com/forums/showthread.php?t=4714
http://www.aquaticplantcentral.com/...ons/1888-tag-amano-article-04-06-issue-2.html

And he often says that his critters are lively/active.
My critters weren't (of course except those small fishes which were very immune to
CO2 level), at least during the day. Yes, they still ate, even reproduced.
But they only seemed lively when the light was out with CO2 off and air pump working.

Now at 37 BPM, all the critters seem very happy. More strangely, the plants pearl
the same. Weird. I believe I'd tried lower bubble rate before, but the plants didn't
respond as good. It has been like this for a month now, go figure...

 

[Hallen]

I'm using bubble and a drop checker which I regularly move around the tank to check if Co2 is spread as much as possible (since it isn't homogeneous). I dont have enough money for a PH controller and I don't really see that much of an advantage of using one. I'm using a timer so it turns on the Co2 supply an hour before the lights go on and turns it off an hour before the light go out. Works like a charm, the nice little Co2 egg from Dennerle is always light green, no signs of heavy breathing among the fish. I do have some minor surface rippling.

I dont change the Co2 after trimming or water changes, never had any trouble even tho I have a small tank. I've got to add tho, I do water changes in the evening so Co2 wont be lost and the extra oxygen is nice for the night.

Btw you can still gas the fish with a PH controller, since it'll keep adding Co2 until the set PH is reached (waterchange). Makes me wonder tho, how much will the PH fluctuate with a set ammount of bubbles?

 

[Gilles]

Thank you for your reactions guys, i'm hoping on some more.

 

[hbosman]

I don't have much to add to what has already been said. I use 4kdh water in two drop checkers on either said of the aquarium. I just tweak the needle valve very slowly over the course of a full day, until my drop checker fluid looks green with a tinge of yellow. After the drop checker color is where I think I want it, I use a PH test kit to get the PH number. Since drop checkers take quite awhile to display changes in PH, I like to know what is "normal" using a PH test kit as well. That way when I make any setting changes, bubble rate, power head relocation, I can get quicker feedback of the CO2 concentration. It is convenient that my tank water must have a kdh close to 4 because the test vial color matches my drop checker color when the CO2 concentration is 30 ppm.

I used to use two timers. One for the lights and one for the CO2 solenoid so I could start bubbling CO2 an hour before the lights came on but, I just use one timer for both lights and CO2 now. In the morning, my drop checkers are still yellow green even though CO2 has been shut off since 10:00 PM. I do have surface ripple as well but, the CO2 in my aquarium doesn't seem to dissipate that quickly. One timer makes it much less messy behind the tank.

 

[pepetj]

I use a field/lab grade CO2 test kit from Hach. It is not perfect but I figure it has less error of measurement than the drop checker. Drawbacks: one of its reagent decays if exposed to temperatures over 25C or below 10C. So finding a place in the refrigerator that remains within this range might be problematic. I used an electronic thermometer with memory for higher and lower temperatures measured to figure this out. Also one of the reagents is considered a real fire hazardous material and cannot be shipped by air. I had to wait over eight months to get this reagent once.

As far as pH controller, I'm not there yet but probably will sooner than later. The main drawback I see with these units is the often probe cleaning and calibration needed to be confident it is indeed working reliable in the pre-set range.

Drop Checkers are an easy, quick way of at least screen our dissolved CO2 probable readings.

An industrial lab grade CO2 monitor hit the market recently, it's rack mounted and is beautiful. Tom commented on this unit but I figure it's really expensive and not cost effective for our needs.

Pepetj
Santo Domingo

 

[barbarossa4122]

From what I have read, it looks like my bps is too high but, my fish are behaving OK. I have 2 bps for the 30g breeder, 2.5 for the standard 55g and 0.5 for the 10g. My DCs turn almost yellow in about 4-6 hrs into an 8 hr co2 cycle. According to this old post by Tom, I should cut the bps rate in half:
http://www.aquaticplantcentral.com/...ons/1888-tag-amano-article-04-06-issue-2.html

For a 135-175 gal I'll use abiout 3 bubbles a sec, 90-125 around 2 bubble sec, 40-80 1 bubble sec, 20-30 gal around 1 every 2 sec, 10-20 gal/ one bubble every 3 sec etc.
These are just estimations but they are not too far off.

Thanks for the links Nipat.

 

[nipat]

Well, now I know bubble rate is so unreliable to communicate.

Now I split my CO2 source to two reactors with IV kits as TheKillHaa's video
http://www.youtube.com/watch?v=5RxQgj09bMc

My connection is regulator -> Coke bottle DIY bubble counter with standard
air tube -> Y splitter > two IV kits -> two DIY reactor.

The bubble rate in the two IV kits is about 3-4 times the bubble rate in the
Coke bottle. The different is bubble size.

 

[barbarossa4122]

Bubble size now ? Lol, I use these BCs and these diffusers:

I guess my bubble sizes and the diffusing are the same in my 3 tanks. I already cut the bps in half and I'll see how the DCs will look at 12 noon when co2 shuts off.

 

[yme]

ehm....

I would go for option 3! pH-controler in combination with drop checkers.

As you know, I use the oxyguard CO2 meter to directly measure dissolved CO2. So I don't need a drop checker.
However, after each water change, I measure my CO2 levels. sometimes, the CO2 level differs after the WC more than 10 ppm! So basically I adjust my pH-controler after every WC to get again my target CO2 level: 55 mg/l.
The difference in CO2 levels is, I think, directly related to the way I prepare my water: 100% osmosis water and than adding back sera mineral salt. I use a conductivity meter to measure when I reached 300 uS. but sometimes I dose a bit too much or too little, which gives rise to a different KH and therefore a different CO2 level in the tank.

But since almost nobody owns a co2 meter, I would for sure go for my "option 3"!

greets,

yme

 

[Tom Barr]

I spot check and then run a data logger for 2 CO2 systems.
But...........I've gotten good enough to know what the growth should look like and fine tweak it by eye.

I do the slow methodical adjustment method, the plants are the test kits.
Algae if you are way off.

I do slow adjustment and have never stressed my fish doing this method.
I've been doing it 18 years though.

This added the right amount regardless of a test method.

Now I do go back and measure the CO2 critically.
Ranges?

About 40-50ppm for some tanks, up to 60-80 ppm for others for day time ranges.
Night?
Depends on the filter, wet drys, 2-3ppm.
Canister?
10-20-30ppm even.

O2 is an important factor for the fish also.
So I measure that in conjunction with CO2.

This requires observation and patience however.
Nutrients are easy, so is measuring light if you have the meter.

CO2 is the devil though for many.

 

[barbarossa4122]

Some say that you should get to lime green or optimal co2 in an hour otherwise, the co2 system you are using is "lagging". Now, how the heck can one do this using such a low bubble rate. I am not arguing but, the more I read about this the more confusing the information/advice gets. And, no one seems to have a clear black or white answer. Frustrating, to say the least.

 

[nipat]

Yep, frustrating.

Formerly 2-4 hrs lagging was the norm.
And now they raise the bar to just 1 hr?
Whoa, what's next then

 

[barbarossa4122]

Yep, frustrating.

Formerly 2-4 hrs lagging was the norm.
And now they raise the bar to just 1 hr?
Whoa, what's next then

Lol, co2 standards/bars are very high. I got to live with it.