Seachem Dosing Calculator
Enter the total volume of your aquarium.
Recommended Dose:
Common Tank Size Dosing Chart
| Tank Size (US Gal) | Recommended Dose (mL) |
|---|---|
| 10 | 0 |
| 20 | 0 |
| 29 | 0 |
| 40 | 0 |
| 55 | 0 |
| 75 | 0 |
What is a Seachem Calculator?
A seachem calculator is an essential tool for any aquarist, from beginner to expert, who uses Seachem’s popular line of water conditioners and supplements. These products are concentrated and require precise measurements to be effective and safe for aquarium inhabitants. Overdosing can be harmful, while underdosing can render the product ineffective. This calculator removes the guesswork, providing accurate dosing instructions based on your specific aquarium volume and the chosen product, ensuring a healthy and stable aquatic environment.
Seachem Dosing Formulas and Explanation
The core of any seachem calculator is the dosing formula provided by the manufacturer. These formulas vary significantly between products.
The general principle is:
Dose = (Aquarium Volume / Product Treatment Volume) * Product Recommended Dose
- Seachem Prime®: The standard formula is 5mL for every 200 Liters (50 US gallons) of water. It’s used during water changes to neutralize chlorine and chloramine.
- Seachem Flourish Excel™: This has two formulas. An initial dose of 5mL for every 40L (10 US gallons), and a subsequent daily dose of 5mL for every 200L (50 US gallons).
- Seachem Stability®: For new tanks, it’s 5mL per 40L (10 US gallons) on day one, followed by 5mL per 80L (20 US gallons) daily for 7 days.
| Variable | Meaning | Unit | Typical Range |
|---|---|---|---|
| Aquarium Volume | The total water capacity of your tank. | Gallons or Liters | 5 – 200 |
| Product | The specific Seachem chemical being used. | N/A | Prime, Excel, etc. |
| Calculated Dose | The final amount of product to add. | mL | 0.1 – 50 |
For more advanced topics, check out our guide on aquarium water chemistry.
Practical Examples
Example 1: Water Change with Seachem Prime
You have a 55-gallon aquarium and are performing a 25% water change. You need to treat the new water.
- Inputs: Aquarium Volume = 55 gallons, Product = Seachem Prime. The dose should be based on the total tank volume for simplicity and safety, as overdosing Prime slightly is safe.
- Calculation: (55 gal / 50 gal) * 5 mL = 5.5 mL
- Result: You should add approximately 5.5 mL of Seachem Prime to the aquarium.
Example 2: Daily Dosing of Flourish Excel
You have a 20-gallon planted tank and want to add a daily carbon source.
- Inputs: Aquarium Volume = 20 gallons, Product = Flourish Excel, Dose Type = Daily Dose.
- Calculation: (20 gal / 50 gal) * 5 mL = 2.0 mL
- Result: A daily dose of 2.0 mL of Flourish Excel is recommended.
How to Use This Seachem Dosing Calculator
Using this seachem calculator is straightforward:
- Select Product: Choose the Seachem product you intend to use from the dropdown menu. The calculator will automatically adjust the formulas.
- Enter Tank Volume: Input the size of your aquarium and select whether the unit is in US Gallons or Liters.
- Select Dose Type: For products like Flourish Excel or Stability, choose whether it’s an initial dose or a regular maintenance dose.
- Review Results: The calculator instantly displays the precise amount of product to add in milliliters (mL). It also provides a helpful chart for common tank sizes.
Understanding your results is a key part of our beginner’s guide to fishkeeping.
Key Factors That Affect Seachem Dosing
- Actual Water Volume: Large rocks, substrate, and decorations displace water. Your 55-gallon tank might only hold 50 gallons of actual water. For precise dosing, this should be considered.
- Plant/Animal Load: Heavily planted tanks may require more frequent or larger doses of fertilizers like Flourish Nitrogen. High bioloads may require emergency dosing of Prime to detoxify ammonia spikes.
- Water Change Schedule: The frequency and volume of your water changes directly impact how often you need to use products like Prime.
- Concentration of Tap Water Chemicals: If your municipal water has very high levels of chloramine, Seachem recommends you can safely double the dose of Prime.
- Product Expiration: Always check the date on the bottle. Expired products can lose their effectiveness.
- Measurement Accuracy: Using proper measuring tools like a syringe or graduated cylinder is more accurate than using a bottle cap.
For a deeper dive, explore our articles on advanced planted tank care and managing your aquarium bio-filter.
Frequently Asked Questions (FAQ)
1. Is it safe to overdose Seachem Prime?
Slightly overdosing Prime is generally safe. Seachem states you can use up to 5x the normal dose in an emergency (e.g., high nitrite spike). However, routine massive overdosing should be avoided.
2. How often should I dose Flourish Excel?
After the initial dose, Excel can be dosed daily or every other day for best results in a planted aquarium.
3. Do I dose for the whole tank volume or just the water I changed?
For dechlorinators like Prime, it’s recommended to dose for the entire volume of the aquarium, not just the new water. This ensures any existing toxins are also neutralized.
4. Can I use this seachem calculator for other brands?
No. This calculator is specifically calibrated for the concentrations and formulas of Seachem products. Using it for other brands will result in incorrect and potentially dangerous dosing.
5. What’s the difference between the “Initial Dose” and “Daily Dose” for Excel?
The initial dose is a larger, introductory amount used on the first day or after a major water change (>40%). The daily dose is a smaller, regular maintenance amount to maintain carbon levels.
6. Why does Stability need to be dosed for 7 days?
This ensures a robust colony of beneficial bacteria is established to handle the aquarium’s bioload, effectively preventing “New Tank Syndrome.”
7. Can I add the products directly to my tank?
Yes, but Seachem recommends adding products like Prime to the new water before adding it to the aquarium for better distribution.
8. What do I do if I have a tank size not listed in the table?
The main calculator at the top of the page allows you to input any custom tank volume for a precise calculation.
Related Tools and Internal Resources
If you found this seachem calculator useful, explore our other resources for dedicated aquarists:
- Aquarium Cycling Calculator: Plan and track your tank’s nitrogen cycle.
- Planted Tank Fertilizer Guide: Learn about macro and micronutrients for your aquatic plants.
- Fish Compatibility Chart: Check which species can live together peacefully in your community tank.