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Hi there

Do any Aussies out there use a rented BOC gas bottle for CO2 injection. I have found out some LFS don't know if the thread on their regulators are "Australian Standard thread" or not. They need to be to fit the BOC bottles.

Edit: I've now found I can get an adaptor from BOC to solve this for $29.95 + GST (part no. 105621)so no more worries there.

BOC (the people who can rent the gas bottle for $9.00 a month) tell me I can buy a regulator from them for $122.33 plus GST (part no. 105207). This regulator includes what they call a Flow Meter. The Flow Meter is apparently the same as a Needle Valve (so say BOC). Do any of you know what a Flow Meter is and if you do, would you agree it's the same as a Needle Valve?

I'm wondering if any of you out there have used these regulators from BOC and if you think the Flow Meter would work for me. I don't really know at this stage what a Needle Valve even does, so I thought I'd ask opinions here?

Also thought that if this does work, it would be useful for other Aussies to know, as it is a lot cheaper than buying regulator from LFS, or buying one of the complete kits.

I hope someone can let me know of their experience or knowledge of Flow Meters.

Cheers
TW

Not sure if I posted this in the wrong forum. Moderators, do you think this should be in Technical Tinkering instead?

If so, can you please move this thread for me. Thank you.

Cheers
TW

Hi,
I'm not sure if a flow meter will work. Generally speaking
a flow meter consists of a glass tube with a very small
hole drilled through it from one end to the other. In it
a small round bead is placed and lines are etched on the
outside and are usually marked in ml/some time usually
ml/hour. As you increase the output from the tank,
the bead will rise up inside the flow meter indicating
that you are using the gas at some rate per minute, or
per hour. This system is fine for administering Oxygen
in a medical situation, but lacks the ability to measure
in very small amounts.

For our uses, we need bubbles per second, and the normal
beginning is to set the rate at 1 bubble per second, see
what that amount of CO2 does to the tank pH over a 12 to
24 hour period, and then readjust from there. We stop
raising the injection rate when we reach a saturation
point between 15 and 30mg/l. We use a needle valve in
conjunction with a bubble counter. The bubble counter
is a glass or plastic container with two connections
for hoses. From one of the connections a tube extends
down into the cylinder.
The cylinder is filled with water, and the
source of the CO2 gas is connected to the long inner tube.
The reactor or diffuser is connected to the other. You open
the bottle of gas, set the regulator for about 1 pound,
and then adjust the needle valve for 1 bubble per second.

This could go in TT or here in Planted Aquaria.
I'll leave it here so everyone who uses CO2 in their tanks
can see your question. You should have more input here
than in TT.

Hope this helps.

Frank


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

Thanks for the response.

I've checked it out further. Yep, flow meter won't work. It will only be accurate to rate of 1 litre per minute. Below that rate, it will be guess work. So, back to the drawing board.

Edit: PS, well that's not quite the full story. They told me there was another place for me to ring that could sell me an extra part to do the job for about $80 - but I've given up on this idea now as I'm not much of a DIY & it's sounding a bit tricky for me. Will buy my own regulator from on-line supplier. I only mention this in case there are any other Aussies who want to follow up on this. They had a phone number to give me, but I didn't take it down. If anyone's interested, the technical people at BOC seem happy to help and spent a lot of time trying to solve the problem.

Cheers
TW