# When do you switch off your CO2?



## parotet (5 Feb 2015)

Hi

This was my last pH profile (2 bps, inline diffuser, 60 cm tank, spraybar, DC yellow at lights on; probably improved by now as I have lots of biomass and I have increased the bubble rate) and you can see what happens when I switch off my Co2 one hour before lights off



It's incredible how fast the Co2 is lost... I was wondering, especially when I increase the bubble rate from 2 to 3 bps, if Co2 can be switched off two hours before lights off. My guess is that even if the co2 is rapidly degassed plants will have more than enough with 5 hours of Co2 super pumping. But my guess is that this can be very difficult to measure, I mean if 2 hours before lights off plants will suffer for low CO2 levels. I know UKAPS tutorial says that the last part of the photoperiod is not so important but... when do you switch off your CO2?

Jordi


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## kirk (5 Feb 2015)

Hello mate, I have tried 2 hrs before lights in my previous tank. But I'm having a nightmare with this one.  I've been doing the same but I think it gasses off quicker as I've no live stock I'm going to leave this running now 24 until this bit of gas runs out the change the bottle. I will then change the timer for an hr before lights off.  So many factors to consider, surface turn over flow rate water depth style of scape.  Bps too. As I have no shrimp or fish I'm just gassing away.


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## 3kris3 (6 Feb 2015)

My co2 comes on an hour before my lights and goes off half an hour after. I've never had a fluctuation in my ph and my plants seem to like it


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## Mr. Teapot (6 Feb 2015)

When I did a pH profile it looked just like yours. My gas goes off 2hrs before the light. Plants seem to be OK with it.


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## parotet (6 Feb 2015)

Was it Clive (Ceg4048) who said in a thread he was pumping CO2 only for 5 hours (and only during 3 hours at the beginning of the photoperiod)? Anyone remember this or is it my imagination? I guess it is a matter of which levels of Co2 you are able to keep even if you are degassing/not pumping... Not having problems with critters but I love to see clear cristal water in my tank and this only happens 1 hour at the end of the photoperiod. At midday it's fine but at the end of the day it's more like a huge box plenty of SevenUp!

Jordi


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## pepedopolous (6 Feb 2015)

I hate the 7 Up look and it's such a pity that my tank looks like it until 8 in the evening. If I could get away with turning the CO2 off earlier it would be great. 

At the moment CO2 = 12:00 to 20:00 (8 hours) Lights = 14:00 - 22:00 (also 8 hours).

P


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## Iain Sutherland (6 Feb 2015)

Get a reactor and it's never an issue 


Sent from my iPad using Tapatalk


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## pepedopolous (6 Feb 2015)

Iain Sutherland said:


> Get a reactor and it's never an issue



Name me a user-friendly, effective reactor that you can buy (no DIY please).

P


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## Downhillmonkey (6 Feb 2015)

Despite the mixed reviews, I'm having success with the Sera 1000.  No 7up.  Similar co2 injection rate to inline diffuser.  Running it via an empty Ehiem 2217 with an APS pre filter.


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## foxfish (6 Feb 2015)

pepedopolous said:


> Name me a user-friendly, effective reactor that you can buy (no DIY please).


 There seems to be a huge gap in the market!! A basic vortex design just seems to be the missing link!


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## Andy Thurston (7 Feb 2015)

parotet said:


> Was it Clive (Ceg4048) who said in a thread he was pumping CO2 only for 5 hours (and only during 3 hours at the beginning of the photoperiod)? Anyone remember this or is it my imagination? I guess it is a matter of which levels of Co2 you are able to keep even if you are degassing/not pumping... Not having problems with critters but I love to see clear cristal water in my tank and this only happens 1 hour at the end of the photoperiod. At midday it's fine but at the end of the day it's more like a huge box plenty of SevenUp!
> 
> Jordi


I'm pretty sure i've read a few posts by clive stating co2 is more critical at lights on
My co2 currently comes on 2.5hours before the lights and goes off 5.5hours before the lights go off
Lights ramp up and down for 4hours with 2 hours at 100% in between giving me 10hours total photoperiod


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## Drpuzzled (7 Feb 2015)

Is expenses the main reason people don't dose 24/7?
I've a much more stable ph/co2 level dosing 24/7, my ph moves by 0.05 ph in a 24hour period.
Well when my atomiser us failing, Ffs
I keep the rank at 6.6 ph 30ppm co2


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## Andy Thurston (7 Feb 2015)

Drpuzzled said:


> Is expenses the main reason people don't dose 24/7?
> I've a much more stable ph/co2 level dosing 24/7, my ph moves by 0.05 ph in a 24hour period.
> Well when my atomiser us failing, Ffs
> I keep the rank at 6.6 ph 30ppm co2


I do it because its hard work lifting a 6kg co2 cylinder in and out of a cabinet while kneeling down It was last changed about a year ago
I could also say I'm trying to reduce my carbon footprint but that would be untrue


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