Can you find cheap co2 fire extinguisher and can they be refilled?
I did find a
5 LB. STEEL CO2 CYLINDER – RECONDITIONED for $40 online ($12 shipping for me). It has been recertified which mean it can be refilled for another 5 years before needed recertification.
If I were to do co2 I would just get the co2 from my local brewing store, seems easier than jury-rigging a fire extinguisher. Benefits to a brew store is also that they're likely to be found in rural locales too since waaay more people brew than keep fish haha. They would probably also have a good amount of the plumbing you would want too (minus the diffuser, with brewing you just force pressurize to carbonate your beer). Please tell me if this is something someone has already explored and it didn't work out, I don't want to be suggesting ideas that dont work in practice!
To reply to both of you:
It's always best to play it safe - which is understandable. I looked around online for a while and found "some" videos and guides on rigging a co2 only extinguisher for the aquarium. It's definitely not unheard of, just doesn't seem widely talked about these days - likely because of all the co2 systems on the market now compared to when that article was written (like 2010 I think? Would have to look again).
Far as cost, I plan on doing more research into the extinguisher differences themselves, as there are multiple classes of them dependant on the type of fire they are most likely to encounter. From my warehouse experience, if I remember right, class b extinguishers are co2. Extinguishers advertised as co2 only seem to be $100 or so, but there are a lot of cheaper options that may also be co2 only. I found some empty ones new for around $25 that need to be refilled.
*Edit: just crossed my mind, I'm sure we could find the sds sheets for any extinguisher we were to look at to see exactly what the gas inside is comprised of.
@mcordelia makes a good point of locale/rural compressed gas suppliers for servicing. You could also check with commercial compressed gas suppliers like AirGas (I know they're in the US not sure about elsewhere) but they do have storefronts you can go into for services/supplies. These companies would likely have the best direction or services to refill a co2 only extinguisher, or possibly even just sell a comparable tank size of co2 that they could refill as needed. Welding supply companies could also point in the right direction I bet (depending on the person you get to talk to).
To recertify, I would assume you could call companies such as AirGas (I use to order all my gases through them as an industrial Buyer II) they have about anything you could want, and can even mix things to your need. Not sure if they would refill a fire extinguisher, but - they could definitely direct you to someone that could if not. If they wouldn't, they likely have smaller cylinders you could just rent or buy and have them filled with co2.
I assume we could also call our local fire departments for better direction on refilling/recertifying a co2 only extinguisher. However, I think the biggest part that worries me is making sure I have good quality equipment to handle the task at hand (looking at 5-15 lb.-ers personally).
Not a project to be frugal with spending on.
I'll reach out to a couple places today and see if I can't find some direction for us as far as maintenance of the tank itself goes. Will post later.