A little less guesswork.
Seachem Cupramine calculator
Cupramine — choose freshwater or marine fish treatment
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
Jump to a section
Freshwater or marine copper treatment?
Choose freshwater or marine fish mode before calculating. Seachem specifies two additions 48 hours apart, with half the marine amount in freshwater and a tested copper concentration maintained afterward.
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.
Freshwater — half the marine amount
| Stage | Amount or action for 100 L |
|---|---|
| Day 1 | 1.25 mL |
| After 48 hours | 1.25 mL Test copper before redosing; the label says not to redose without testing. |
| After the second addition | Maintain 0.25 mg/L copper for 14 days, using a compatible copper test. |
Marine fish — standard marine amount
| Stage | Amount or action for 100 L |
|---|---|
| Day 1 | 2.5 mL |
| After 48 hours | 2.5 mL Test copper before redosing; the label says not to redose without testing. |
| After the second addition | Maintain 0.5 mg/L copper for 14 days, using a compatible copper test. |
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
Visual help: Read your bottle label · Read a small liquid scale. Teaching diagrams do not replace your bottle or measuring-device instructions.
Remove invertebrates and the specified chemical filtration; stop UV/ozone. Do not combine Cupramine with other medicines or reducing agents such as conditioners/ammonia binders. Test copper before redosing.
Product-specific checks from the calculation record
- Remove invertebrates. Do not use in a reef system or combine with other medications or reducing agents, including ammonia binders and dechlorinators.
- Stop UV/ozone and remove chemical media as instructed. The calculated additions do not replace copper testing, and this tool does not calculate test-driven top-ups.
Is the second amount permission to redose without a test?
No. Seachem explicitly requires testing. A volume calculation cannot measure copper already present, adsorption or concentration changes.
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.
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Seachem Cupramine, 50 mL
View on Amazon US (affiliate link) — Seachem Cupramine, 50 mL; opens in a new tabCheck the selected bottle, formulation and label before buying. These links do not select a treatment or change your dose. Prices, sellers and availability are shown on Amazon. About these links.