Seachem MultiTest Phosphate – Precise Phosphate Test Kit for Marine & Freshwater

Catch Phosphate Before It Fuels an Algae Bloom

Rising phosphate quietly feeds nuisance algae and stresses sensitive reef inhabitants. Without an accurate reading, you can't tell whether your water is clean or heading for trouble.

MultiTest Phosphate measures inorganic phosphate to less than 0.05 mg/L, producing a unique, easy to read yellow-green-blue color range in marine and freshwater. It performs over 75 tests and includes a reference sample for validation, so you can trust every result down to a precision of 0.001 mg/L.

MultiTest Phosphate is developed by Seachem Laboratories, the chemistry-driven company founded in 1979 in Madison, Georgia, USA, whose kits are formulated in-house by its own chemists. That reagent-based engineering is why MultiTest kits are known for sensitivity and accuracy: the phosphate chemistry produces a distinct, easy-to-read color range and ships with a reference sample so you can validate the kit itself and be confident in every reading.

1. Prepare your water sample per the kit.
2. Match the yellow-green-blue color to read your phosphate level.
3. Confirm accuracy against the included reference sample.

Keep phosphate in check and your water crystal clear. Add to cart.

What It Does

This kit measures inorganic phosphate to less than 0.05 mg/L, producing a unique easy to read yellow-green-blue color range in marine and freshwater.

Details

MultiTest Phosphate performs over 75 tests and contains a reference sample for validation. Range: 0-3.0 mg/L. Precision: 0.001-0.1 mg/L.

Why Seachem MultiTest Phosphate

• High sensitivity: measures inorganic phosphate to less than 0.05 mg/L with a precision of 0.001-0.1 mg/L across a 0-3.0 mg/L range.
• Easy-to-read results: a unique yellow-green-blue color range makes matching your phosphate level clear and straightforward.
• Great value per kit: performs over 75 tests, so a single kit covers long-term monitoring.
• Built-in validation: includes a reference sample so you can confirm the kit is reading accurately.

Best For

Ideal for reef keepers guarding sensitive corals, planted-tank and freshwater aquarists chasing nuisance algae, and anyone who wants precise, ongoing phosphate monitoring. It works in both marine and freshwater systems.

FAQ

Freshwater or saltwater? It works in both marine and freshwater aquariums.

How many tests does it perform? The kit performs over 75 tests and includes a reference sample for validation.

How precise and what range? It reads inorganic phosphate to less than 0.05 mg/L, with a range of 0-3.0 mg/L and precision of 0.001-0.1 mg/L.