Diy Co2 With Airston

[Phenz]

I'm looking to get an airstone and set up a yeast reaction DIY CO2 unit.

i'm in the process of gathering together all the ingredients for a yeast CO2 production unit.

2litre soda bottle
smaller bottle to ensure only gas transfered into tank
check valve
then into an airstone.

I would like the asthetics of an airstone in the tank so i would like to have the option of switching on an auxillary pump to augment the airflow creating a more effervecent look.

would connecting a pump onto the feeder tube via a Y section create a suction on the CO2 setup and ruin the effect?

is there a way to combine these two factors via a single pipe to a single airstone?

 

[peter-pecker]

As far as i know if you add a air pump you will cause exess surface movement & co2 will be lost far quicker than oterwise would be, so i would keep surface movement to a bare minimum.

 

[Phenz]

i understand that but i was thinking of having an airstone which i could switch on from time to time and watch the fish play in the bubble stream.

i used to have a bit of surface movement from my overhead filter unit but i've topped up the tank so the fall is minimal and the surface is bearly broken. i have 3 mid-sized plants and 2 small in a 20gallon,tall tank.

i just thought i'd set up CO2 becuase i want to have more plants and want them to thrive.

Is an airstone increasing oxygenation of the water by breaking the surface counterproductive to adding CO2?

would a non-airstone method of introducing CO2 be better?

 

[Spinal]

Quick reply... not a good idea from any perspective.

DiY CO2 (assuming you mean yeast co2 mix) wont work well with an airstone. In fact, CO2 and airstones don't mix. At all... Why? Simple, 2 reasons:

1- CO2 is acidic. Very acidic in fact. In a matter of weeks, your airstone will become part of your substrate, leaving you with a tube (and alot of dissolved airstone fragments on the bottom of your aquarium).

2- Airstones with air pumps provide surface agitation. CO2 doesn't stay dissolved in water too easily (try leaving a bottle of coca-cola open for a couple of days... thats CO2 in there....). Now immagine if you shook the bottle... all of a sudden, you would lose CO2 exponentially.

My recomendation, if you, like me like the look of air bubbling through your tank, is to go for CO2 overkill. Go pressurised, pump in enough CO2 to get 20ppm even with the airstone (thats what I'm doing). You can go DiY pressurised too... a paintball system will cost you 15 pounds (see the link in my sig); I am now experimenting with a new system. All in all it costs 21/22 pounds, (and refills cost 7/10pounds); but it has the advantage of being able to get refills ANYWHERE in the UK (both mail order and in certain chains). I'll post a how-too as soon as I have 15 mins free time.

Michele

 

[Phenz]

i'd seen your post during my seemingly exhastive search of DIY CO2. ideally i'd like to set up a system/routine which is fairly straight forward. i've had an aquarium for a few weeks and i'm lerning what i can. i'd like it to be fairly non-commital whereby i can set it going and leave it untill the next bought of tank maintence.

i live in the centre of glasgow and don't have a car or access to one. I think it would be difficult for me to get to a paintball place but there might be a builders merchant or a place where i can get a tank refilled.

If i were to be able to set up a pressurised CO2 semi-diy setup, how long would the tank last before it needed refilling?

 

[Spinal]

Ok, just a quick run through until I have time to write this up properly. If there is a Halfords near you, pop by and ask for:
1 x Sip brand Regulator for MIG welding (9.xx pounds; almost 10)
1 x Sip brand disposable CO2 cylinder (not mixed argon/Co2, you want pure Co2)(usually 9.xx pounds, I found them on special offer and got them for 7.xx)
1 x airline, OD 4mm, ID 2.5mm (the important bit here is the OD, not the ID, the ID the bigger, the better) (I got mine for 30p per meter)


How to set ut up... uhmm, check the regulator is turned to the off position, screw it onto the CO2 Cylinder. Push one end of the airline into the push-in connector on the regulator, and shove the other end onto your diffuser; (my glass diffuser has a wider end than my pipe, so I boiled some water, shoved a chopstick into the pipe as far as it would go and heated the pipe with the water. Once the pipe was very supple, I slided it onto the diffuser and let it cool).

Turn regulator knob until you get bubbles

As for how long they last, it really depends on how much CO2 you pump in. I ran my paintball cylinder for 2 months, at 4/5bubbles per second, and it still had CO2 left in it when I started experimenting with the halfords CO2....

Michele

 

[Phenz]

that sounds like quite a sound solution.

I don't have a halfords around, but i've got all the bits and bobs i need for the yeast reactor and being a mechanical engineer i'm looking forward to making my CO2 bottle setup.

it'll be the only setup mathematically modeled to identify the stress concentrations, friction factors, dynamic viscosity and an efficiency rating

 

[voo]

Airstones aren't good for CO2 diffusion. The bubbles they release are too big and as a result most of the CO2 reaches the surface without diffusing into the water, therefore being wasted.



You'd do much better with a ceramic type airstone. They release much finer bubbles. Alternatively, ladders are effective but take up more room in the tank / more visible.



If you're adding CO2, you want as little surface movement as possible. You'll want some for the oxygen exchange (if you're heavily planted, it wont matter so much as the plants will provide enough oxygen). The surface movement helps release the CO2 from the water.



When you start adding CO2, make sure you keep an eye on your pH levels. The CO2 will cause it to drop.





Spinal - The CO2 you got from Halfords, what is it meant to be used for?

 

[vic]

A really good read for a start in the world of CO2. It will answer a lot of questions that you don't even have yet!

http/www.qsl.net/w2wdx/aquaria/diyco2.html

 

[B.D.S]

sorry to jump on a thread but i'm using my diy co2 set-up (so far at a cost of £2.49!)with one of these connected to it

it seems to be working without any probs providing a fine mist, has anyone used one of these before and run into any problems?

 

[Phenz]

the plan at the moment is to use a 100% cotton filtertip for rolling tabacco and stick it in the end of the tube. the bubbles are very fine and i've heard of it working in other cases.

 

[voo]

Cotton dissolves over time in water. some people use it to tie plants to wood as it'll dissolve and leave the plants attached to the wood by their roots. Will be interesting to see if what you plan works