calculatorsonline.co.uk
Planted Tank Light Intensity Calculator
Work out watts per gallon and lumens per litre for a planted aquarium and classify the light level.
💡 Free Online Tool
⚡ Instant Results
📊 Clear Comparison
🔒 100% Free Tool
Free Aquarium Tool
Compare Your Options And Get Clear Answers
Work out watts per gallon and lumens per litre for a planted aquarium and classify the light level.
Planted Tank Light Intensity Estimator
Enter your numbers below for an instant estimate.
0
💡 Tip: More light needs more CO2 and nutrients, otherwise algae takes over.
How It Works
Key concepts behind this calculator
1
Enter Values
Fill in each field with your own numbers.
2
Calculate
Results update as you change the inputs.
3
Review
Read the breakdown and the explanation.
4
Adjust
Change values to compare scenarios.
Quick Reference Guide
Planted Quick Guide
Typical values for reference.
| Class | Watts per Gallon | Lumens per Litre | Plants |
|---|---|---|---|
| Low | Under 0.5 | Under 25 | Anubias, ferns |
| Medium | 0.5 to 1 | 25 to 50 | Most stems |
| High | Over 1 | 50+ | Carpet plants |
| Very high | Over 1.5 | 75+ | Needs CO2 |
| Rule of Thumb | Check inputs | Use as a guide | Round sensibly |
Common Questions
Planted Tank Light Calculator FAQ
Answers to common questions about this calculator.
Medium light suits most beginners.
Light watts divided by tank gallons.
Use lumens or PAR instead.
Reduce light hours or intensity.