Tweaking CO2 levels

[phillarrow]

I have recently changed my pressurised CO2 system and am having some difficulty in adjusting the bubble rate. I currently have the main valve on the CO2 bottle just over half open and am using the fine adjuster attached to the solenoid to control the amount but it is VERY sensitive and I seem to be fluctuating between having at least 5bps and having 1bps that slowly drops off to zero. Any advice?

 

[aaronnorth]

Is the fine adjuster a needle valve? If not then get one of these to control it properly.

 

[LondonDragon]

You need to give it time when you make an adjustment, turn it slowly, then give it 5 or 10 minutes and see whats its like, then move it a little again, and wait another 5 or 10 minutes. Until you have the desired rate, pressure inside the tube means it won't go to actual rate straight away.

 

[a1Matt]

Some tips from my (limited) experience....

Exactly what LondonDragon says! - Be very precise, make small changes at a time and patience is a virtue!

I take a 10sec video of the bubble rate before and after adjustment.
You can then use this video as a reference point. I check it against the buble rate 30min, an hour and day after any adjustments to check that the rate hasn't changed without me realising it (as per the previous post things take time to settle down). I also use it when putting a new cylinder on, it helps you to get the bubble rate the same as the last one.

It is worth checking that you do not have any water backfeeding into your siphon tubing (I assume you have a check valve, but water can still lead up to where the check valve is!) as this can make the flow of bubbles somewhat erratic thus making it harder to see the results of any adjustments to the flow rate.
When I do have water in the tubing I simply take off the tubing from the reg and blow really hard through it to clear the water.

HTH