Dry Ice For Co2

[des22]

Has anyone thought of or tried using "dry ice" for co2 injection into a planted tank?

I heard that dry ice is pure co2. Suring that should work? Use the same DIY co2 sytem instead of using a yeast and suger cocktail. Use dry ice which i believe can be bought from any ice supplier.

 

[aaronnorth]

it is extremely cold though and it would cause temperature change problems. You also have to work out how much CO2 you are injecting.

 

[des22]

Maybe one can design a system for the gas warm up abit? Anyone got any ideas.
Maybe a chamber where the gas sits for a bit before leaving to react in the water or sump.
Or maybe get the gas to react in a small tank or camber with water and a heater to warm it up before sending it to the main tank.

 

[aaronnorth]

how much is it anyway?

 

[K-Holed]

To be honest, dry ice sounds like a nightmare. Firstly, it's dangerous stuff. The extreme temprature can cause burns to human flesh. Secondly, it'd be hard to regulate the CO2 it gives off. At room temprature, it rapidly turns to gas, giving you more CO2 than you'd sensibly want. Thirdly, you'd need a way to store dry ice you weren't using, this is impracticle in a home setting.

 

[Rooster]

Has anyone though of decomposing bio matter.... or running a car exhaust ? This is getting daft, you can get it in nice, safe, convenient cylinders you can turn off at night..... why look for harder alternatives ?

Sorry - but I felt it needed saying !

 

[maximinimus]

Has anyone though of decomposing bio matter.... or running a car exhaust ? This is getting daft, you can get it in nice, safe, convenient cylinders you can turn off at night..... why look for harder alternatives ?

Sorry - but I felt it needed saying !

You could spend all day blowing into an airline connected to your co2 diffusor.

Or you could make a DIY system but use cabonated soft drinks to release CO2 instead of yeast!

 

[Rooster]

where in the UK would you buy "dry ice" ?

 

[maximinimus]

where in the UK would you buy "dry ice" ?

Chemical/Industrial Gas suppliers, normally you can only buy it in 10KG amounts though.

 

[des22]

You two

's i was just asking, no need to get funny. Its not about finding harder ways its about finding more effective ways. EDIT: is this not what this DIY section is about or im i in the wrong place??

Now carring on--
Dry ice is very easy to get hold of where i stay. Its not hard to work with just keep it in a container in the deepfreeze. One block of dry ice slowly evaporated would probably give off just as much co2 than the yeast method.

If you had to put the dry ice in a cooler box the box would keep cold and the dry ice would slowly give off co2 as it evaporates.

Compressed co2, is just as cold. Like the co2 you get for paintball. Have you ever seen a co2 bottle leak and get it on your hand or seen it spray on somthing? Ever wondered way they say dont get co2 in the paintball gun. It will instantly freeze the o rings and damage the internal parts.

When co2 is regulated by the time it reaches the tank it would have warmed up a bit right? So if one gave co2 from the ice time to get to the tank it would also have warmed up enough.

 

[aaronnorth]

You two

 

[Mr Bliss]

A much more plausible way to produce CO2 at will would be to mix sodium bicarbonate (baking soda) with citric acid using some kind of an automatic doser (a new use for an automated fish-feeder?) or drip system. Bicarbonate and citric acid react and produce CO2, H2O and sodium citrate, of which CO2 quickly evaporates. This is the reaction that happens when you add Alka-Seltzer to water. Instead of citric acid, I guess acetic acid (vinegar) would be simpler (and cheaper?) to get, but acetic acid is volatile and some of it would end up in the tank. Some (all?) coffee machine cleaning powders are pure citric acid.

The way I would intuitively do this is, mix 1 - 10% citric acid (would need to do testing to find suitable concentration) into a container and install some kind of a drip system to inject bicarbonate (dissolved in water) into it. Or inject citric acid into a bicarbonate solution, either way should work. Or dose a mixture of dry baking soda and citric acid into water, for that matter. Sounds simple and I think you could run a stable system this way, but getting the CO2 into the tank might be a problem since the required pressure in the reaction bottle might make running a stable drip/dosing system difficult. But now that I got going, I think I'll have to do some maths on the chemistry (to see how much CO2 you could get out of a given amount of ingredients, compared to say a yeast bottle) and see if I could devise a simple DIY injection system for this kind of thing...

 

[Rooster]

CO2 isnt cold AT ALL.... all that happens is an endothermic reaction due to the rapid expansion of the gas.... regulate (ie slow the flow of) the gas and this happens to such a small extent as to be nominal.

Still seems daft to go beyond cylinders IMHO......

 

[des22]

Mr Bliss

Have you maybe just found a more effective way than the ancient yeast method? Maybe?
Lets us know how the test results go?

 

[maximinimus]

When co2 is regulated by the time it reaches the tank it would have warmed up a bit right? So if one gave co2 from the ice time to get to the tank it would also have warmed up enough.

Actually CO2 is at ambient temperature, if you get a big release the sudden expansion of the gas absorbs heat from around it, which is what makes things freeze. Released slowly enough the gas will hardly change from ambient temperature.

Dry ice is completely different, it sublimes directly from solid to gas at -78.5*C.

For the system to work effectively, you would need an insulated system to prevent it from melting too quickly, this in itself would cause a problem as you would be pumping a freezing gas straight into your tank.