CO2 at night?

Laith

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Jan 24, 2005
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I've seen that Tom (and others) turn off their CO2 at lights out to avoid excessive CO2 buildup while plants are not using it.

Is this necessary if your CO2 is hooked up to a pH controller? The CO2 saving is minimal anyway because of the amount of CO2 needed to bring the pH back down to where you want it when the lights go on...

I tried hooking up my pH controller (pH set to 6.6) to a timer and when the pH controller kicks back in an hour before lights on, the pH has gone up to 7.3. At my bubble rate, the pH comes back down to 6.6 after about 2-3 hours.

I'm a bit worried about the 0.7 pH swing and am thinking of taking the controller off of the timer as their shouldn't be any risk of CO2 excess at night? :confused:
 

Paul

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Jan 24, 2005
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Re: CO2 at night?

I had the fish gasping at the surface a while ago when I was using the DIY C02 kits. I now use a bottled c02 and just run an airstone a few times during lights out, as far as I am concerned, C02 is cheaper than a ph controller :)
 

Paul S

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Jan 24, 2005
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Re: CO2 at night?

I shut my CO2 off one hour before lights out.
CO2 is turned on 2 hours before lighs on.
KH is 5-6
PH is 6.7 - 7.1
Fish are doing very well. Algae is trying to hang on.
At present I'm doing the above function manually but will go back to auto mode when I get my new solenoid valve.
Running CO2 at 24/7 was too problematic. (ie. fish were stressed to the point where some perished)

Above method works well for me but YMMV.

enjoy

Paul S
 

Laith

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Re: CO2 at night?

Thanks but my question was whether people thought it served any purpose to turn off the CO2 if you have a pH controller running...
 

Greg Watson

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Jan 23, 2005
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Re: CO2 at night?

Laith said:
Thanks but my question was whether people thought it served any purpose to turn off the CO2 if you have a pH controller running...

It would not serve any useful purpose to turn it off when you have a pH controller ...

Greg
 

Laith

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Re: CO2 at night?

Thanks Greg, that's what I was looking for! I know it seems pretty obvious but good to have confirmation... ;)
 

Tom Barr

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Re: CO2 at night?

I'll disagree, you can use it with a pH control, just for the hours "on" during the day and turn it off during the night, not that there would be a need for this, but you could do it if you desired.
So generally, yea, no need, but you could cook up a way and perhaps some reason.

Regards,
Tom Barr
 

jippalbert

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Jan 30, 2005
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Re: CO2 at night?

Not to hijack this thread but If my KH is around 5-7 It is ok to simply shut off the regulator at lights out? No Major PH swings ?


My KH is currently coming up around 3 . Having a hard time with GH and the Sera test kit.

JK
 

Tom Barr

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Re: CO2 at night?

Should be fine

Regards,
Tom Barr