I have several tanks using co2 and several brands of co2 regulators: UNS, CO2 Art, Fzone. On all of them I find the adjustment to be incredibly sensitive and even the tiniest adjustment making a difference. is that normal? I’m wondering if lowering the regulated pressure might help. I run mine between 35-40. I wish someone made a digitally controlled regulator to eliminate this issue.
Welcome to ScapeCrunch
We are ScapeCrunch, the place where planted aquarium hobbyists come to build relationships and support each other. When you're tired of doom scrolling, you've found your home here.
Adjusting needle valve on CO2 regulator - sanity check
- Thread starter Noahspapa
- Start date
- Tagged users None
This is normal. Unfortunately, most of these regulators all come from some of the same factories across the world with similar qualities. Just different branding. I've personally seen Tommy at ARC brand regulators with his brand, that are literally the exact regulators UNS sells for a higher price.
The needle valves on all of these regulators just suck, especially for the size tanks most hobbyists use. It's the #1 reason I've paid high prices to have @Bettatail create amazing regulators with incredible, fine needle valves.
On those old regulators, turning the knob approx 1-2 degrees could increase the bubbles per second by about 50%. It was infuriating.
With the needle valves that I have on these regulators, an entire turn clockwise will reduce the flow by 10% or less. It's amazing.
If your tank is big enough with enough CO2 injection, you could get a flowmeter like the Dwyer 151RMA to help dial in your flow with the bad needle valves. You could also look into buying a needle valve and all the parts necessary to add a secondary inline precise needle valve. Unfortunately most good needle valves start at $60+.
techman81
Well-known Member
A few here including @Naturescapes_Rocco, convinced me to reach out to @Bettatail for help gathering parts to build some custom regulators after a I mentioned having a couple Fzone failures. I will say this about the OTS brands I have, of Fzone, CO2Art, and GLA regulators, the GLA has, by far, the best needle valve of the lot. I'll still use GLA on my current tanks, but the custom regulators will be used for the bigger tanks I set up.
They are terrible, and I feel they are a huge reason that people give up on CO2 or lose fish. The problem isn’t just the cost of aftermarket needle valves, it is sourcing the right ones. There doesn’t seem to be a ‘go to’ option that is easily available in all places.
A good example is my tank at the moment. I have it currently set where it reaches equilibrium at 35ppm CO2, if I turn it up the smallest turn I can manage, it reaches 60 ppm. I want it somewhere in the middle but cannot for the life of me turn it a smallest enough turn to make that happen. I do have a pH controller, but it turns off at 0.04 pH under my setting, and turns back on at 0.04 above my setting, so a 0.08 pH bounce up and down, which I am hoping to avoid. I prefer to use it just as a safety cut out, rather than a setting for the tank.
I am hoping the flow meter I have ordered will be appropriate… but I am nervous about aliexpress parts.
I am hoping the flow meter I have ordered will be appropriate… but I am nervous about aliexpress parts.
Second that
for an OTC regulator kit, GLA has the steadiest and finest degree of control I've found. It's their biggest selling point 
Nothing can touch the stability and precision of a lab grade valve on a custom regulator post-body
Swagelok / NuPro makes excellent low flow micrometer metering valves, frequently available on eBay
however @Bettatail or @Alanle can best help wade through all the many variations to identify the right one
Last edited:
- Thread starter
- #7
Thank you all for your input.
would it be possible to just upgrade the needle valve in a fzone regulator ? Or does it have to be a custom kit? Asking for a 24 gallon tank. Thanks
Since the needle valve is integrated into the manifold block on these regulator kits, in theory if you could lay hands on one of the old discontinued GLA pro 5 Style manifold blocks it may mate up with the F Zone manifold block 
Parts of these will turn up on eBay from time to time.
That being said I can't say if the old Pro-5 style GLA needle valve was internally similar to the Pro DS1 needle valves.
Alternately you could possibly buy a manifold block with the integrated needle valve from GLA, or used, remove the needle valve and install it in your FZone manifold block.. If the diameter is the same which I don't know
Parts of these will turn up on eBay from time to time.
That being said I can't say if the old Pro-5 style GLA needle valve was internally similar to the Pro DS1 needle valves.
Alternately you could possibly buy a manifold block with the integrated needle valve from GLA, or used, remove the needle valve and install it in your FZone manifold block.. If the diameter is the same which I don't know
I agree with you 100%. My solution was to buy an inline needle and a sensitive flow meter - similar to the dwyer one suggested here.
It was the only way I could control the flow the way I wanted. It's a pain in the ass and it's added expense.
Next time around I will investigate a custom made solution for sure.
It was the only way I could control the flow the way I wanted. It's a pain in the ass and it's added expense.
Next time around I will investigate a custom made solution for sure.
