freshwater - diy CO2

[Fay]

Warren I'm a little worried about the fish at night, I have put a small powerhead on a timer to come on when the lights go off, plus the external filter moves the top of the water do you think this is ok, should I put the thingie on the powerhead to make bubbles or is it better without, and or should I be doing something else.

[spooky]

Basically in the light plants convert CO2 to O2 and in the dark they convert O2 to CO2 but in smaller quantities.

Sorry to be pedantic, but this isn't worded too well and it reads as one of those "common misconceptions" I learnt about in 5th form science many years ago and still annoys me. Plants are always converting O2 to CO2 (i.e. breathing). The O2 production while the lights are on is a lot greater than the O2 use, so on balance (and for the sake of this argument) it is true.

I'll stop being picky now.

[breakaway]

I have a question for you people with DIY CO²:

How do you regulate how much CO² goes into your tank?

[livebearer_breeder]

well you could put a spliter on the tubing going from the DIY bottle in the air tubing to your tank.

Shae 250

[Thunderstorm]

Hiya

I use a little plastic needle valve on my system. Its set for about a bubble per second depending on yeast fermentation progress.

You can get them from ya LFS.

Setting it up is tricky i found as you have to wait untill the yeast is brewing nicely to get enough gas coming out to play with.

I'll take some pics of my CO2 system and post them up tomorrow.

Thanx Peter

[critter_guy]

hey from hunting and fishing they sell little co2 casiters for co2 powered guns would that work making up a system and conecting one of those on but there onlu small bout 7cm long how long would it last???

[livebearer_breeder]

those are for airsoft guns and pistols, It would to rather expenisve ot be replace those seeing as they are pressurised, and setting up a system to make use of the Co2 would cause all of it to shoot through into the tank, and then you'd have to go buy another. I have these in my airsoft guns, and most of the time i cant even be bothered replaceing them becuase of the expense.

Shae 250

[Ira]

And they'd probably only last a few days.

[steve slack]

hey

what is a good mix for a co2 system in a 1.5 litre bottle?

thanks

[spooky]

I use a teaspoon of yeast, half a cup of sugar and 750 ml of warm water with the sugar well dissolved. It lasts me three weeks to a month, I haven't ever tried to optimise this mix since it works fine for my system. Exact results depend on the temperature of the bottle, how much of the CO2 dissolves in the water and what the phase of the moon is.

[Thunderstorm]

Hiya

Some pics of my CO2 setup

Just click on the pic to enlarge.

Thanx

peter

[Warren]

Sorry to be pedantic, but this isn't worded too well and it reads as one of those "common misconceptions" I learnt about in 5th form science many years ago and still annoys me. Plants are always converting O2 to CO2 (i.e. breathing). The O2 production while the lights are on is a lot greater than the O2 use, so on balance (and for the sake of this argument) it is true.

I'll stop being picky now.

No, thats completely ok, be picky as much as you like. You are correct and when we give information to others it's good to get it as correct and clear as possible. What I should have written instead is:

"Basically in the light plants convert CO2 to O2 (in much high quantites than O2 gets converted to CO2) and in the dark they only convert O2 to CO2. "

It's still not that clear but you get the general idea. It's the net quantity of C02 and O2 that matters. During the day the net O2 production is higher and during the night the net CO2 production is higher...