should I turn it of at night or not

Tom Barr

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Jan 23, 2005
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It's not used at night, having it at high levels when the it's not being used serves no purpose and makes life harder on fish when there's no added O2 from the plantas.

Regards,
Tom Barr
 

dapellegrini

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Do you turn it back on before the lights come on to get your CO2 levels up when the plants start their daylight cycle? Or is the nightly swing not enough to make a difference?

I currently have mine running 24/7 with no averse effects, besides possibly wasting some CO2 at night...
 

dapellegrini

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dschmeh: How much CO2 do you loose in the night time? i.e. Where is your PH driven to with CO2 in the day, and where is it in the morning when the lights come on?
 

sevenrider860

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Dec 19, 2006
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I wonder about the PH drop also. When I turn the CO2 off at night my PH will rise from 6.7 to 7.4 by the time the CO2 is turned back on and the PH drops back to 6.7. I am not trying to target a specific PH, but I thought the idea was to avoid PH swings. I do have an airstone that turns on when the lights go out to ensure there is adequate oxygen at night.

Are the nightly PH swings a "don't care"?? Turning the CO2 off at night would be nice since the only thing it does during that time is maintain the PH level.

Thanks for any opinions!

Brian
 

dapellegrini

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I used to use an airstone at night but no longer find the need. I bet that some of that large swing you have there is because of the airstone. Try turning the airstone and the CO2 off at night.

I have been told repeatedly that pH swings due to CO2 don't matter one bit.
 

Professor Myers

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Aug 24, 2006
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sevenrider860;12795 said:
I wonder about the PH drop also. When I turn the CO2 off at night my PH will rise from 6.7 to 7.4 by the time the CO2 is turned back on and the PH drops back to 6.7. I am not trying to target a specific PH, but I thought the idea was to avoid PH swings. I do have an airstone that turns on when the lights go out to ensure there is adequate oxygen at night.

Are the nightly PH swings a "don't care"?? Turning the CO2 off at night would be nice since the only thing it does during that time is maintain the PH level.

Thanks for any opinions!

Brian

What are your respective KH, and GH levels ? at dkh 5, and dgh 6 running air in my tickle filter at night my ph rises to 7.4 in the morning, and will return to 6.7 as well, once the Co2 and lighting resumes and eventually flatlines at ph 6.6 until nightfall. Without air it will rise to PH 7.1

I haven't noticed the fish stressing any, but the plants and livestock both DO seem to enjoy the additional air at night. I'd rather the swing was lower, but just haven't observed any adverse affect so long as the KH and GH are stable. Maintaining the PH is all well and good, but plants are every bit as greedy for o2 at night and I suspect it drives or fascilitates nutrient uptake.

Oddly enough on the organic system utilizing a yeast reactor I located the bottles adjacent to the massive Hamilton ballast under the stand, so once the lights go out Co2 production drops by half effectively accomplishing the same thing. Weird, but effective...HTH. Prof M