Seachem Prime® Bonus Size – 325 mL
Seachem Prime® Bonus Size 325 mL is a highly concentrated aquarium water conditioner for both freshwater and saltwater systems. Prime® removes chlorine and chloramine from tap water and temporarily detoxifies ammonia, nitrite, and nitrate so they can continue to be processed by the aquarium’s biological filtration.
This 325 mL bonus-size bottle provides more product than the standard 250 mL size, making it a convenient option for aquarists who perform regular water changes or maintain multiple aquariums.
Key Features
- Complete concentrated aquarium water conditioner
- Suitable for freshwater and saltwater aquariums
- Removes chlorine
- Removes chloramine
- Detoxifies ammonia
- Detoxifies nitrite and nitrate
- Does not alter aquarium pH
- Can be used during aquarium cycling
- Can be added directly to the aquarium or to replacement water
- Highly concentrated formula
- 325 mL bonus-size bottle
Product Information
- Brand: Seachem
- Product: Prime®
- Size: 325 mL Bonus Size
- UPC: 000116043007
- Product Type: Aquarium water conditioner
- Use: Freshwater and saltwater
What Prime® Does
Prime® conditions tap water by removing chlorine and chloramine before the water is introduced to aquarium livestock.
It also temporarily binds ammonia, nitrite, and nitrate into less harmful forms while leaving them available to the aquarium’s beneficial bacteria for biological processing.
Prime® does not permanently remove ammonia, nitrite, or nitrate from the aquarium. Proper biological filtration, water changes, and maintenance are still required.
Standard Dosage
Use 5 mL for every 50 gallons of new water.
- 10 gallons: 1 mL
- 20 gallons: 2 mL
- 25 gallons: 2.5 mL
- 50 gallons: 5 mL
- 75 gallons: 7.5 mL
- 100 gallons: 10 mL
One full capful is approximately 5 mL. Seachem notes that each cap thread represents approximately 1 mL for smaller doses.
Approximately How Much Water Does 325 mL Treat?
At the standard dose of 5 mL per 50 gallons, a 325 mL bottle can condition approximately 3,250 gallons of new water.
Actual usage will vary if higher doses are used for chloramine, ammonia, or nitrite emergencies.
Directions for Water Changes
- Determine how much new tap water is being added.
- Dose Prime® based on the volume of new water whenever possible.
- Add Prime® to the replacement water before it enters the aquarium.
- Add temperature-matched replacement water to the aquarium.
Prime® may also be dosed directly into the aquarium. When dosing directly into the tank, Seachem recommends basing the dose on the total aquarium volume.
Using Prime® During Aquarium Cycling
Prime® may be used during aquarium cycling when ammonia or nitrite is present.
The product binds these compounds temporarily while keeping them available to beneficial bacteria, so Prime® does not stop the biological cycling process.
Emergency Dosing
Seachem states that Prime® may be dosed at up to 5 times the normal amount in emergencies involving elevated ammonia or nitrite.
If ammonia or nitrite remains elevated, Prime® may be redosed according to Seachem’s instructions while the underlying cause is corrected through water changes, filtration, and aquarium maintenance.
Important Use Notes
- Use whenever adding or replacing tap water.
- A sulfur-like odor is normal for Prime®.
- Small dark specks in the bottle may also occur and are considered normal by Seachem.
- Prime® does not replace regular water changes or biological filtration.
- Do not rely solely on water conditioner to control chronically high ammonia, nitrite, or nitrate.
- Always investigate and correct the source of poor water quality.
Prime® and Ammonia Testing
Some ammonia test kits may produce confusing or false readings after Prime® is used because the product binds ammonia rather than removing it from the water.
Seachem specifically notes that Nessler-based tests may not provide reliable readings after Prime® use. Always follow the instructions for the specific test kit being used.
Does Prime® Affect pH?
No. Seachem states that Prime® is non-acidic and does not alter aquarium pH when used as directed.
Freshwater and Saltwater Use
Prime® can be used in both freshwater and saltwater aquariums.
It is suitable for:
- Freshwater community aquariums
- Planted aquariums
- Cichlid aquariums
- Goldfish aquariums
- Shrimp and snail aquariums when used according to directions
- Marine fish aquariums
- Reef aquariums
- Quarantine and holding systems
Storage
- Keep the bottle tightly closed.
- Store at normal room temperature.
- Keep away from excessive heat and direct sunlight.
- Keep out of reach of children and pets.
Seachem states that Prime® does not have a fixed expiration date when properly stored.
Frequently Asked Questions
How much Prime® do I use?
Use 5 mL for every 50 gallons of new water under normal conditions.
How much water does the 325 mL bottle treat?
At the standard dosage, approximately 3,250 gallons.
Can Prime® be used in freshwater and saltwater?
Yes. Prime® is designed for both freshwater and marine aquariums.
Does Prime® remove ammonia?
It does not physically remove ammonia. It temporarily binds and detoxifies it while allowing the biological filter to continue processing it.
Can Prime® be used during cycling?
Yes. Seachem specifically states that Prime® may be used during aquarium cycling.
Why does Prime® smell like sulfur?
A sulfur-like odor is normal and does not indicate that the product has spoiled.
Does Prime® expire?
Seachem states that Prime® will last indefinitely when stored properly.
Available at Tropical Treasures Wyo
Seachem Prime® Bonus Size 325 mL is available at Tropical Treasures Wyo in Cheyenne, Wyoming, when in stock.
Eligible dry goods are available for shipping.
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