CO2 Injection
- Thread starter djlen
- Start date
Hey,
I put together a diy co2 bottle and it seems to be working fine. But reading through these posts it looks like one bottle for my 40 gallon tank isn't going to cut it. How many should I use?
I put together a diy co2 bottle and it seems to be working fine. But reading through these posts it looks like one bottle for my 40 gallon tank isn't going to cut it. How many should I use?
I use a Co2 can.
It is just a spray can of CO2. It has a small rubber tube attached to the outlet of the can and that goes into my tank where it is attached to a plastic container on suction cups attached to my tank walls. I just "spray" the CO2 a little bit every other day.... But my worry is that the CO2 is just dissolving out the surface... There is no diffuser.
It is just a spray can of CO2. It has a small rubber tube attached to the outlet of the can and that goes into my tank where it is attached to a plastic container on suction cups attached to my tank walls. I just "spray" the CO2 a little bit every other day.... But my worry is that the CO2 is just dissolving out the surface... There is no diffuser.
My Co2cents worth
Since this is a sticky I thought I would pipe in and comment on some of the older subjects.
Co2 on or off at night?
It is done both ways successfully. Turning it off at night by using a solenoid control has the distinct advantage of the CO2 bottle lasting twice as long. Leaving it on at night also has some advantages. When your CO2 density is at 20ppm the plants do not use all that gas. Having an amount that high provides the plants with more access to “usable” CO2 molecules. Think of it like catching rain drops on your tongue. If it’s raining lightly you will catch less then when it’s raining hard but you never get all the drops. As an example: if you set the CO2 to 20ppm during peak photosynthesis hours then tested again in the middle of the night any differences would likely be less then the precision of your over the counter test kits. Therefore; the concern about -pH bounce from unused CO2 at night is not that big of a deal (natural ecosystems experience some pH fluctuations from night to day for a variety of reasons). On the other hand, turning the CO2 off at night can significantly reduce the amount and lead a +pH bounce. Also, plants can begin photosynthesizing within an hour of the light coming on, so if your CO2 levels are low because the system was off at night then some growth time is being wasted.
DIY Co2
Use a bucket of water with a heater to increase production. I don’t think putting the heater in the 2L bottle is a good idea. It’s enough of a hassle to unscrew the caps and change them without dealing with an extra power cord, and one small heater can heat a bucket with several bottles. I put the heater on the same timer as the lights (not for reducing CO2 at night but to help the mix last longer between changes). Use a reactor!!!! DIY or buy one they make a huge difference with a yeast set up. I ran a 45g tall on three 2L bottles (changed one weekly) and had levels as high as 35ppm easy.
Why use CO2?
I’ve seen some beautiful natural tanks that didn’t use any CO2, but the best tanks I’ve seen containing abundant varieties and lush dense growth used CO2.
Since this is a sticky I thought I would pipe in and comment on some of the older subjects.
Co2 on or off at night?
It is done both ways successfully. Turning it off at night by using a solenoid control has the distinct advantage of the CO2 bottle lasting twice as long. Leaving it on at night also has some advantages. When your CO2 density is at 20ppm the plants do not use all that gas. Having an amount that high provides the plants with more access to “usable” CO2 molecules. Think of it like catching rain drops on your tongue. If it’s raining lightly you will catch less then when it’s raining hard but you never get all the drops. As an example: if you set the CO2 to 20ppm during peak photosynthesis hours then tested again in the middle of the night any differences would likely be less then the precision of your over the counter test kits. Therefore; the concern about -pH bounce from unused CO2 at night is not that big of a deal (natural ecosystems experience some pH fluctuations from night to day for a variety of reasons). On the other hand, turning the CO2 off at night can significantly reduce the amount and lead a +pH bounce. Also, plants can begin photosynthesizing within an hour of the light coming on, so if your CO2 levels are low because the system was off at night then some growth time is being wasted.
DIY Co2
Use a bucket of water with a heater to increase production. I don’t think putting the heater in the 2L bottle is a good idea. It’s enough of a hassle to unscrew the caps and change them without dealing with an extra power cord, and one small heater can heat a bucket with several bottles. I put the heater on the same timer as the lights (not for reducing CO2 at night but to help the mix last longer between changes). Use a reactor!!!! DIY or buy one they make a huge difference with a yeast set up. I ran a 45g tall on three 2L bottles (changed one weekly) and had levels as high as 35ppm easy.
Why use CO2?
I’ve seen some beautiful natural tanks that didn’t use any CO2, but the best tanks I’ve seen containing abundant varieties and lush dense growth used CO2.
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Diy Co2
After reading through the posts here, I thought I'd mention some observations I made using it.
First off I always had a problem with those cheap check valves you get at the LFS eventually getting stuck open rendering them useless. Usually from getting wet. Fortunately I never had any problems with one getting stuck closed, which I'm assuming could have resulted in a big mess.
I also never had a problem with the water syphoning all the way back to the bottle, although it was close a few times, but never had a flood.
One of the things I did to eliminate this problem was to set the bottle on top of the light fixtures above the tank. This fixed the syphoning. I think I would still use the check valve close to the bottle and far from the tank, just to keep it from getting wet, which should eliminate the check valve eventually getting stuck.
Setting the bottle on the top of the light fixtures had an additional side effect, they lasted days longer. I'm assuming this is because they were slightly warmed by the heat comming off the light fixture. After reading the other posts I think this would be easier and cheaper than the other suggestions mentioned for warming the bottles.
After reading through the posts here, I thought I'd mention some observations I made using it.
First off I always had a problem with those cheap check valves you get at the LFS eventually getting stuck open rendering them useless. Usually from getting wet. Fortunately I never had any problems with one getting stuck closed, which I'm assuming could have resulted in a big mess.
I also never had a problem with the water syphoning all the way back to the bottle, although it was close a few times, but never had a flood.
One of the things I did to eliminate this problem was to set the bottle on top of the light fixtures above the tank. This fixed the syphoning. I think I would still use the check valve close to the bottle and far from the tank, just to keep it from getting wet, which should eliminate the check valve eventually getting stuck.
Setting the bottle on the top of the light fixtures had an additional side effect, they lasted days longer. I'm assuming this is because they were slightly warmed by the heat comming off the light fixture. After reading the other posts I think this would be easier and cheaper than the other suggestions mentioned for warming the bottles.
Hey, guys. I'm new to the CO2 Game. I have a 72g planted tank and am wondering how many bubbles per second I should be using. It isn't too densly populated with plants, but it seems I am using too much CO2. I'm already running at over 2 to 2.5 bubbles/second. I have a really good reactor so I'm getting very good diffusion. I test my pH and it is still above 7.0, could this just be because my water is so hard. If I brought my GH down would this effect the way my CO2 changes my pH?
I also have quite a good light. It is a 260w, 48 inch, compact flourescent, full spectrum light.
Also, I know some of you guys must have a similar sized, heavily planted tank. How much CO2 do you need?
Lyle
I also have quite a good light. It is a 260w, 48 inch, compact flourescent, full spectrum light.
Also, I know some of you guys must have a similar sized, heavily planted tank. How much CO2 do you need?
Lyle
bringing the kh down to around 6-7 will allow for your co2 ppm to increase because it's not being absorbed by the buffer; and your ph will drop.
plants and fish do great with soft, acidic water; i run a ph of 6.5 (probe controlled) and a kh of roughly 6 to get 61-67ppm of co2. under poor conditions that's enough co2 to stress and kill fish, but the acidic/soft water really promotes nutrient uptake in the plants and with high light you'll have pearling on avg by around hr 5-6 of your light cycle which provides more o2 than needed in the water column. during the off hours when the plants switch to co2 production you wanna turn off your injection if you go for high ppm; or things die.
most people tend to shoot for 20-30ppm of co2 (there's a lot of charts online to help you achieve that) because it's safer and easier to manage while providing more than enough co2 for plants to do photosynthesis. hard water makes growing plants exceptionally difficult because you can't get the co2 ppm up to a useful amount.
somewhere around 50gl diy becomes inefficient and simply can't provide enough co2 so pressurized is what you want to eventually go to if you're trying to do a high tech tank (2+ wpg / micro + macro dosing / co2).
i also just wanted to point regarding the first post of this thread; co2 is not a nutrient.
plants and fish do great with soft, acidic water; i run a ph of 6.5 (probe controlled) and a kh of roughly 6 to get 61-67ppm of co2. under poor conditions that's enough co2 to stress and kill fish, but the acidic/soft water really promotes nutrient uptake in the plants and with high light you'll have pearling on avg by around hr 5-6 of your light cycle which provides more o2 than needed in the water column. during the off hours when the plants switch to co2 production you wanna turn off your injection if you go for high ppm; or things die.
most people tend to shoot for 20-30ppm of co2 (there's a lot of charts online to help you achieve that) because it's safer and easier to manage while providing more than enough co2 for plants to do photosynthesis. hard water makes growing plants exceptionally difficult because you can't get the co2 ppm up to a useful amount.
somewhere around 50gl diy becomes inefficient and simply can't provide enough co2 so pressurized is what you want to eventually go to if you're trying to do a high tech tank (2+ wpg / micro + macro dosing / co2).
i also just wanted to point regarding the first post of this thread; co2 is not a nutrient.
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