A little less guesswork.
Seachem Flourish calculator
Flourish comprehensive supplement — not Excel or a separate macro supplement
Read the product guide and worked examples ↓
Clear amounts. Visible assumptions.
Your calculation, explained
Choose a product and enter the water you’re actually dosing.
- Check the exact product and formulation.
- Use measured water, or make an explicit estimate.
- Review the amount, source and any schedule.
Product guide · edited 28 October 2026
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Which Flourish product does this calculate?
This covers the original Flourish plant supplement: 5 mL per 250 L per application, once or twice weekly under Seachem’s directions. It is not Flourish Excel or a dedicated nitrogen, phosphorus or potassium supplement.
Worked examples
These illustrations use 100 L of measured water, without a decor deduction. Choose the matching stage or formulation above for your own water volume. They do not select a treatment or establish livestock suitability.
Once or twice weekly
| Stage | Amount or action for 100 L |
|---|---|
| Once or twice weekly | 2 mL |
Example only. Your calculation above uses your own inputs. Small amounts and powder fractions still need equipment that can measure them reliably.
Before you measure
Match the bottle name. Seachem recommends refrigeration three months after opening. Nutrient percentages on the analysis are not the quantity added by a single dose.
Product-specific checks from the calculation record
- When also using Flourish Trace, Seachem advises alternate days. Refrigeration is recommended three months after opening.
Is Flourish the same as an all-in-one NPK fertiliser?
Seachem distinguishes its micro/trace supplement from macro-nutrient supplementation. Compare the nutrient role before substituting products.
Sources and next steps
Seachem manufacturer directions →
Manufacturer page consulted 28 October 2026. Match the exact bottle and leaflet; editorial review does not establish diagnosis or compatibility.