Fluval CO2 Bubble Counter
Water type
Freshwater
Fits
Fluval Pressurized CO2 Kit 45g, Fluval Pressurized CO2 Kit 88g, Fluval Pressurized CO2 Kit 95g
Part no.
17550
Fluval CO2 Bubble Counter
A drop-in bubble counter that lets you count and set your CO2 injection rate at a glance. Fitted between the regulator and diffuser on a Fluval pressurized CO2 kit, it gives you a clear view of each bubble so you can dial in a consistent dose for planted freshwater tanks.
Key features
- Visual dosing check – count bubbles per second to confirm your CO2 rate without guesswork.
- Fits Fluval's pressurized CO2 kits – a direct replacement or spare for the 45 g, 88 g and 95 g kits.
- Helps protect cylinder life – dialling in a moderate, steady rate rather than overdosing extends how long a cylinder lasts.
Specifications
| Item number | CO204 |
|---|---|
| Barcode | 015561175500 |
| Fits | Fluval Pressurized CO2 Kit 45 g, 88 g and 95 g |
| Water type | Freshwater, planted tanks |
Compatibility, spares and supersession
This bubble counter is designed as a spare or replacement part for Fluval's three pressurized CO2 kit sizes – 45 g, 88 g and 95 g. It is not designed for Fluval's low-pressure Bio CO2 systems, which use their own bubble counter.
Setup, use and dosing
Fit the bubble counter in the CO2 line between the regulator and the diffuser so bubbles are visible as they pass through. As a starting point, Fluval recommends around one bubble every 2–4 seconds for a moderately planted tank, which is also the rate that gets the most life out of a cylinder – at that pace, a cylinder typically lasts around 2–3 weeks. Increase or reduce the rate to suit your plant mass and CO2 drop-checker readings.
Care and maintenance
Clean periodically to keep bubble visibility clear. If you're running the diffuser this counter feeds, its ceramic disc has a working life of around 3–6 months and should be swapped when CO2 output visibly drops.
Suitable for, and not suitable for
- Suitable for freshwater planted tanks running a Fluval pressurized CO2 system.
- Not suitable for Fluval's low-pressure Bio CO2 Pro systems, which use a different bubble counter.
Warranty and delivery
Covered by Fluval's standard consumer warranty against manufacturing defects, in addition to your rights under Australian Consumer Law. Ships standard parcel delivery.
Common questions
Will this fit my Fluval CO2 kit?
It's designed for the 45 g, 88 g and 95 g Fluval Pressurized CO2 Kits. It isn't designed for the low-pressure Bio CO2 Pro range.
What bubble rate should I run?
Around one bubble every 2–4 seconds is a reasonable starting point for a moderately planted freshwater tank, adjusted against your plant growth and CO2 drop-checker.
Does a faster bubble rate mean more CO2?
Yes, and it also drains your cylinder faster – Fluval's recommended rate is chosen to balance plant growth against cylinder life.
