How to get the right amount of CO₂ for aquarium plants?
Want your aquarium plants to bubble and stay algae-free? The key is the right amount of CO₂.
This article teaches you how to use a cylinder generator (baking soda + citric acid reaction CO₂ generator) paired with a diffuser to get it done easily.
Why add CO₂?
The natural CO₂ in your aquarium is far from enough.
Consequences of CO₂ deficiency: yellowing plants, stunted growth, algae outbreaks.
What you need
Cylinder generator (baking soda + citric acid reaction CO₂ generator) : safe, easy to get ingredients
Diffuser: breaks CO₂ into micro-fine bubbles for high dissolution efficiency with no waste
Three steps to find the "right amount"
Step 1: Setup
Add the ingredients according to the instructions. Place the diffuser opposite the filter outlet so bubbles spread throughout the tank.
Step 2: Adjust the bubble count
|
Tank size |
Recommended bubble count |
|
Under 40L |
1 bubble per 2–3 seconds |
|
60–120L |
1 bubble per 1–2 seconds |
|
Over 120L |
3–4 bubbles per second |
Use a timmer:CO₂ should turn on with the lights (can turn on 1 hour before lights on, turn off 1 hour before lights,Must turn off at night to prevent oxygen depletion in fish and shrimp.
Step 3: Watch your fish and plants to decide
No need for testing — just observe:
|
What you see |
What to do |
|
Plant leaves bubbling, fish & shrimp acting normal |
✅ Keep as is |
|
Fish & shrimp gasping at surface, darting around |
⬇️ Turn down the valve, reduce bubbles |
|
Plants not bubbling, no new growth |
⬆️ Increase bubble count |
Remember:If fish gasp , need to reduce Co2 ; if plantts bubble, its just right.
Common questions:
Q: Are more bubbles always better?
A: No. Too many bubbles can kill your fish and shrimp. Keep it right, not excessive.
Q: My diffuser stopped producing fine bubbles. What should I do?
A: It might be clogged. Soak it in a chlorine-based cleaning solution or replace the diffuser disc.
Q: How long does one batch of ingredients (200g baking soda + 200g citric acid) last?
A: For a 60L tank at 0.5–1 bubble per second, about 30–60 days.
With a baking soda + citric acid generator and a diffuser, you just need to:
Adjust bubble count (refer to the table above)
Turn on/off with the lights (5–8 hours per day)
Watch your fish and plants (reduce if fish gasp, just right if plants bubble)
Master these three steps, and your planted tank will soon be thriving.
Need equipment or accessories?
Visit our website and search for: 【CO₂ Generator】, 【Diffuser】