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I set up a DIY CO2 system yesterday and am wondering if I should turn off my airstone at night? The CO2 seems to be working well but I'm wondering if I'm reducing its effect by leaving the air pump running at the same time. Any info is appreciated.

Dwayne

yes...u r reducing the efficiency of the co2 system by displacing the co2-absorbed faster out of the water.

i have diy co2 in 2 of my tanks..i dont run any airstone...what i do is...making sure theres enuf surface movement for o2.

how big is ur tank...what is wpg..what r the occupants...do u see ur fish gasping for air b4 the lights turn on in the morning??

In most tanks, there is not really a need for airstones unless you need the extra surface agitation or like the asthetics. Not having the airstone on at all will help your CO2 enter the water. Also, you could attatch the airstone to your DIY CO2 if you like the look of an airstone.

I am not a pro in this field, but it appears that there are 2 groups (at least) with 2 distinct opinions. One will tell you that you can run the air stone at night, the other says the opposite. Personally, I don’t think you loose anything while running an air stone at night (guess what side I am on ). Your plants do not need additional CO2 at night (actually they produce it then on their own). I also don’t believe that you would have to wait until the fish gasp in the morning in order to take action.

I also heard that the larger the surface movement in a tank is the more CO2 will leave the water column. This would contradict tanker’s statement above.

I would suggest you do the following:

Test the PH of your tank before the lights go off and then again just before they go on in the morning, while NOT running an air stone. If there is a major difference (ph lower in morning) then you have more CO2 in your tank than you have during the day time. -- Means run an air stone at night.

Now do the same test with the air stone on at night. If there is a major difference (ph higher in morning) then you “blew” the CO2 out of the water (sorry, I am not the most technical person). -- Means DON'T run an air stone at night.

If neither nor is the case, you could go either way without any problems.

Again, I am not really a pro and I currently try to understand the relationship between all these things myself.

Hope this helps,

Ingo

Last edited by Little_Fish at 27-Jul-2005 14:51

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Proud Member of the New Jersey Aquatic Gardeners Club

"I set up a DIY CO2 system yesterday and am wondering if I should turn off my airstone at night?"

Does that mean you run the airstone during the day? That really makes no sense if you do as if you have enough plants they will produce enough O2 during the day.

As for the night time, if your fish are gasping without it, then you need to run it. If they are not gasping, then it's your decision whether you want it or not. Many people don't want to run an airstone as they feel it's a waste to put CO2 into the water and then drive it out by creating surface agitation. Some people disagree and run an airstone anyway, claiming that with plants' respiration of CO2 at night, the CO2 levels rise through the night which will balance the using an airstone. Most people will believe that what they're doing is the correct way of doing things, but as someone who's tried both ways, I can tell you I didn't think there was that much of a difference, certainly not something that would make me decide that one way is the right way.

As for pH swings, they probably will occur to some extent whether you decide to run an airstone or not, but as long as it's not a major pH swing, it will not harm the fish.

Last edited by untitled at 27-Jul-2005 15:17

Thanks for all the quick replies. I've been running an airstone constantly since I first set up my tank. Originally, I had only fake plants in the tank so the airstone was necessary. I've recently replaced all the fake plants with live plants and still plan on adding more. My tank is 20 gallons and my stock list is shown on my profile. I'll test the PH both at night and in the morning to see if there's a difference and let you know the results.

Dwayne

I turn the CO2 off at night.

That solves that easily.
You add it to grow the plants, the plants do not need it at night, therefore do not add it then.

It's quite simple to plug the power hwead or a solenoid into a timer(you can do this by adding a "Tee" and the sloenoid on one end of the tee. When the solenoid closes, this forces gas into the the tank, when it's open(during the day), the CO2 escapes(night))

A powerhead stops running, then the Gas simply bubbles up and escapes. When it's runningm, the CO2 can be sucked into the impeller side and into a reactor/bell/along the back wall downward etc.

Why have something extra to plug in when it's not needed?
We add CO2 for the plants, not to stabilize pH.

Regards,
Tom Barr