Seachem Prime 250 ml

Seachem Prime is a complete, concentrated conditioner that removes chlorine and chloramine while detoxifying ammonia, nitrite, and nitrate — 5x stronger than competing products.

Prime is the complete and concentrated conditioner for both fresh and salt water. Prime removes chlorine, chloramine and ammonia. Prime converts ammonia into a safe, non-toxic form that is readily removed by the tanks biofilter. Prime may be used during tank cycling to alleviate ammonia/nitrite toxicity. Prime detoxifies nitrite and nitrate, allowing the biofilter to more efficiently remove them. It will also detoxify any heavy metals found in the tap water at typical concentration levels. Prime also promotes the production and regeneration of the natural slime coat. Prime is non-acidic and will not impact pH. Prime will not over activate skimmers. Use at start-up and whenever adding or replacing water. Sizes: 250 mL

Nearly all companies manufacture a product that removes chlorine. None of those, however, can compare in quality, concentration, or effectiveness to Seachem's flagship product: Prime. Prime is the second most concentrated De-chlorinator on the market after our own Aquavitro Alpha. A single 100 ml bottle with treat 1000 US Gallons of Tap Water. Prime will remove both chlorine and chloramines from municipal water supplies. Prime also contains a binder which renders ammonia, nitrite, and nitrate non-toxic. It is very important to understand how those two functions work together. All de-chlorinators operate through a chemical process known as reduction. In this process, toxic dissolved chlorine gas (Cl₂) is converted into non-toxic chloride ions (Cl-). The reduction process also breaks the bonds between chlorine and nitrogen atoms in the chloramine molecule (NH₂Cl), freeing the chlorine atoms and replacing them with hydrogen (H) to create ammonia (NH₃). Typically De-chlorinators stop there, leaving an aquarium full of toxic ammonia. Seachem takes the necessary step by including an ammonia binder to detoxify the ammonia produced in the reduction process.

Be very careful when purchasing water conditioners. If your municipality includes chloramines in the water supplies, a standard sodium thiosulfate de-chlorinator is not enough. Prime promotes the natural production and restoration of the slime coat rather than relying on artificial or non-native slime compounds. A further bonus for the reef hobbyist Prime will not over-activate protein skimmers.

Use 1 capful (5 mL) for each 200 L (50 gallons*) of new water. This removes approximately 1 mg/L ammonia, 4 mg/L chloramine, or 5 mg/L chlorine. For smaller doses, please note each cap thread is approx. 1 ml. May be added to aquarium directly, but better if added to new water first. If adding directly to aquarium, base dose on aquarium volume. Sulfur odor is normal. For exceptionally high chloramine concentrations, a double dose may be used safely. To detoxify nitrite in an emergency, up to 5 times normal dose may be used. If temperature is > 30 C (86 F) and chlorine or ammonia levels are low, use a half dose.

Part of managing nitrate and phosphate levels — see our guide to Nitrate & Phosphate for why these two parameters are tracked together.

Freshness & Storage

Every batch we dispatch carries a minimum of 6 months' remaining shelf life. Store this product in a cool, dry place away from direct sunlight, with the cap or inner foil closed tightly after each use.

Returns & Replacement

Returns are accepted within 7 days of delivery, provided the item is unused and in its original packaging. Manufacturer-sealed items cannot be returned once the seal is broken, and sale-priced items are not refundable.

If your item arrives defective or damaged, message us on WhatsApp with your order number — or email us, if you would rather — and we will replace it. Approved replacements are delivered within 3 to 5 business days. Transit damage is covered by insurance on every shipment. If tracking shows delivered but nothing reached you, tell us within 72 hours, which is the reporting window Indian couriers allow. Damage caused during installation or use is not covered; replacement spares for such cases are chargeable.

Full terms are on our Cancellation & Returns page.