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GLA Modular Manifold Block

11 reviews Write a Review
$50.00
GLA Modular Manifold Block G3
GLA Modular Manifold Block G2
GLA Modular Manifold Block G2 vs G3 comparison
SKU:
202123
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GLA Modular Manifold Block G3
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Description

GLA Modular CO2 Manifold Expansion Block

Expand the CO2 distribution capacity of a compatible GLA modular dual-stage regulator with the GLA Modular CO2 Manifold Expansion Block. Each precision-machined block adds one independently controlled CO2 output, allowing an existing GLA PRO-DS or DS-Mini regulator to supply an additional planted aquarium from the same CO2 cylinder.

Each manifold block includes its own precision needle valve and integrated bubble counter, allowing CO2 flow to be fine-tuned and visually monitored for each connected aquarium. Working pressure is shared by the regulator, while CO2 flow is adjusted independently at each manifold needle valve. The modular design allows compatible expansion blocks to be installed quickly and securely as your aquarium system grows.

  • Add one independently controlled aquarium output per block
  • Fine-adjust CO2 flow separately for each aquarium
  • Monitor each output with its integrated bubble counter
  • Expand a compatible GLA modular CO2 system as your aquarium setup grows

Important: GLA manifold blocks are generation-specific. Generation 2 (G2) and Generation 3 (G3) blocks are not cross-compatible and cannot be mixed. Verify your regulator generation before ordering.


Choosing the Correct Version: G2 vs G3

GLA modular regulators have been produced in multiple generations. When adding a manifold block to an existing regulator, the expansion block must match the generation already installed on your regulator.

G2 and G3 manifold blocks are not cross-compatible and cannot be combined on the same regulator.

Compare the needle valve on your existing manifold with the identification details below and refer to the G2/G3 comparison photo in this listing before ordering.

Generation 3 (G3)

  • Needle Valve Shape: Non-tapered
  • Knurled Surface: Knurled texture extends across the full length of the adjustment section

Generation 2 (G2)

  • Needle Valve Shape: Tapered
  • Knurled Surface: Knurled texture extends partially along the adjustment section

Not sure which version you have? Do not guess. Compare your existing regulator with the G2/G3 reference photo in this listing or contact GLA at info@greenleafaquariums.com before ordering.


Compatible GLA Regulator Platforms

The GLA Modular CO2 Manifold Expansion Block is designed for compatible GLA modular dual-stage regulator systems, including:

  • GLA PRO-DS Dual Stage CO2 Regulators
  • GLA PRO-DS Dual Stage CO2 Systems
  • GLA DS-Mini Dual Stage CO2 Regulators
  • GLA DS-Mini Dual Stage CO2 Systems

Not Compatible With GLA GRO: The GLA GRO platform uses a different expansion system and requires the dedicated GLA GRO CO2 Splitter.

Generation Compatibility: The manifold block generation must match the existing regulator configuration. G2 and G3 components cannot be mixed.


Frequently Asked Questions

What does one manifold block add to my regulator?
Each manifold block adds one independently controlled CO2 output, allowing one additional aquarium to receive CO2 from the same compatible regulator and CO2 cylinder.

Can each aquarium receive a different amount of CO2?
Yes. Each manifold block has its own precision needle valve, allowing CO2 flow to be adjusted independently for each connected aquarium.

Do all manifold blocks use the same working pressure?
Yes. Working pressure is set at the regulator and shared across the manifold. CO2 flow to each aquarium is then adjusted independently using the needle valve on each manifold block.

What is the difference between G2 and G3?
G2 and G3 use different needle valve designs and are not cross-compatible. G3 uses a non-tapered needle valve with knurling extending across the full adjustment section. G2 uses a tapered needle valve with knurling extending partially along the adjustment section.

Can I mix G2 and G3 manifold blocks?
No. Generation 2 and Generation 3 manifold blocks cannot be mixed on the same regulator.

How do I know which generation I have?
Compare the needle valve on your existing regulator with the G2/G3 reference photo in this listing. If you are still unsure, contact GLA at info@greenleafaquariums.com before ordering.

Will this fit a GLA GRO regulator?
No. The GRO platform uses a different expansion design. Use the dedicated GLA GRO CO2 Splitter to add additional outputs to a GRO regulator.

Will this fit a DS-Mini or PRO-DS regulator?
Yes, provided the manifold block generation matches the generation already installed on the regulator.

Does the bubble counter measure dissolved CO2?
No. The integrated bubble counter provides a visual reference for gas flow through that output. Actual dissolved CO2 depends on factors including diffusion efficiency, circulation, surface agitation, aquarium volume, and overall CO2 demand.


Support & Compatibility

Return Policy: Due to the technical nature of pressurized aquarium CO2 equipment and the generation-specific compatibility of this component, this item is non-returnable and non-refundable. Please verify whether your regulator requires a G2 or G3 manifold block before ordering.

If you are unsure which version is compatible with your regulator, contact GLA at info@greenleafaquariums.com prior to purchase. We can help identify the correct generation based on the regulator and needle valve configuration.

Warranty

Return Policy: Due to the technical nature of pressurized aquarium CO2 equipment, this item is non-returnable. Qualifying defects remain covered under the GLA Limited Lifetime Warranty and are handled separately through warranty support. Please contact GLA prior to ordering if you need assistance with product selection, installation, or compatibility.

Customer Reviews

11 reviews

  • 5

    GLA Modular Manifold Block

    Posted by Marc on 8th Jan 2026

    Matches the one that came with the regulator exactly. If it works the same as the original I will be a happy camper. Very smooth, very precise and stays exactly where you set it.

  • 5

    Works great

    Posted by Joey on 28th Aug 2025

    Super easy to to attach and works great. GLA always makes good products.

  • 5

    Great product

    Posted by Quality on 1st May 2025

    Really great quality !

  • 5

    Is good!

    Posted by Andrew Erman on 7th Feb 2025

    Easy to install (there is video instruction). Works great once installed. Happy.

  • 5

    I love this system

    Posted by Octavio Flores on 5th Jan 2025

    This system is awesome. its very reliable and easy to adjust

  • 5

    Perfect

    Posted by POW on 18th Jan 2024

    I bought one of these to add a tank to my gla mini modular CO2 system. Installation couldn't have been easier and it works exactly as you'd expect it to.

  • 5

    GLA MODULAR MANIFOLD BLOCK

    Posted by Tom Kuhlman on 10th Sep 2023

    Got this as an add-on for a 3rd planted tank. As with everything with the GLA name on it, it is excellent, and works flawlessly!!!!!!

  • 5

    These are phenomenal

    Posted by Niles Gallespi on 24th Aug 2023

    GLA always had the highest quality metering valve. This valve is no exception, super precise and the curve rate is superior to the crap on everything else.

  • 5

    Love GLA manifold blocks!

    Posted by Jamie Prescott on 12th Sep 2022

    I have 14 on my co2 regulator lol! Yes, it looks totally wild and I have the cylinder anchored. With that said these needle valves are amazing. Super smooth and the bubble rate is not all crazy, its smooth and easy to dial in. Thats why I now have 14 lol.

  • 5

    GLA MODULATOR

    Posted by Thomas Dobbins on 27th Dec 2021

    These are top of the line! Amazing company with amazing employees putting customers first!

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