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CO2 Setup & Schedule
CO2 is the single best thing you can add to a planted tank early. It's not optional if you're serious about growth — and it won't stress your fish if you dial it in right.
The Schedule
8 hrs
CO2, per day — starts 2h before light
If you need more, increase gradually by +30 minutes per week (keep it starting 2h before your light):
| Week | CO2 |
|---|---|
| Week 1 | 8h |
| Week 2 | 8.5h |
| Week 3 | 9h |
CO2
2pm – 10pm Frequency
7 days a week
2pm – 10pm Frequency
7 days a week
Best Practices for CO2
- Use an inline CO2 diffuser. It injects CO2 directly into your filter outflow — more efficient than in-tank diffusers and keeps your tank visually cleaner.
- Run CO2 as high as your tank can safely handle. This helps prevent and control algae. In most cases, that's roughly 2–4 BPS.
- I don't use drop checkers — they're slow and misleading. I push CO2 as high as possible. If fish are fine, you're fine.
How to Dial It In
-
1Start at 1 bubble per second (BPS).
-
2Increase by +1 BPS every 3 days.
Watch your fish
If they begin gasping at the surface → stop CO2 for the day. The next day, resume at the last stable BPS.