Seachem Flourish Phosphorus 250 ml

Seachem Flourish Phosphorus is a precise potassium phosphate solution that takes the guesswork out of dosing phosphorus in planted aquariums.

Product Description

Flourish Phosphorus is a safe solution (4500 mg/L phosphate) of potassium phosphate that takes the guess work out of phosphate dosing. Unlike competing products that mix nitrate and phosphate in a fixed ratio, Flourish Phosphorus (being nitrate free) allows you to dose phosphorus according to the needs of your plants without the risk of overdosing nitrates. When used as directed Flourish Phosphorus will enhance and accelerate the growth of aquatic plants without enhancing algae growth. For maximum benefit use with Flourish Nitrogen and Flourish Potassium.

Unlike competing products, Flourish Phosphorus is entirely nitrogen-free, making it possible to adjust the Phosphorus level in an aquarium without affecting nitrogen levels.

Directions

BEGINNER: Use 2.5 mL (half a cap) for each 80L (20 gallons*) once or twice a week or as needed in response to signs of phosphorus deficiency (e.g. stunted growth, plant dark green). EXPERT: The beginner dose raises phosphorus by 0.05 mg/L (0.15 mg/L phosphate). The ideal phosphate level will vary, but generally ranges from 0.151.0 mg/L. Use MultiTest: Phosphate to monitor phosphate levels. To target a specific phosphate increase, dose according to the following formula: 0.8vp=m, where v= volume of tank in gallons*, p=desired phosphate increase and m=volume of product to use in mL. For example to raise 20 gallons* to 0.1 mg/L phosphate you would use: 0.8*20*0.1=1.6 mL.

Derived from: potassium phosphate

Compatibility

Freshwater planted tanks. Seachem state it is safe for invertebrates such as shrimp.

Dose it only when there is a phosphorus shortfall — stunted new growth and unusually dark green leaves. Surplus phosphate feeds algae, so this is one to test for rather than dose on a schedule.

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.