Seachem Laboratories Reef Phosphorus Supplement 100 mL, 3.4 oz

For the careful reef keeper, sometimes a small bottle is exactly what the tank calls for. Seachem Laboratories Reef Phosphorus Supplement comes in a compact 100ml (3.4 oz) size, perfect for smaller reef systems or for dosing one element with a light touch. Seachem explains that phosphorus is an essential element required in metabolic processes, protein synthesis, and the growth of corals and macroalgae, so keeping it in range supports the living things in your tank.

• Targets phosphorus specifically, giving you a precise way to raise phosphorus concentrations in your reef.
• Seachem notes it raises phosphorus effectively without also adding dissolved organics, so you are not introducing extras.
• Concentrated formula, so even this small bottle goes toward supporting the element your corals draw on.
• Supports the metabolic processes the brand describes as essential to coral health.
• Helps support protein synthesis, one of the building blocks of coral growth the brand highlights.
• Backs the growth of both corals and macroalgae, useful for mixed reef and refugium setups.
• The 100ml (3.4 oz) bottle suits smaller tanks or keepers who want to dose conservatively.
• A low-commitment size if you are introducing phosphorus supplementation for the first time.
• Made by Seachem Laboratories, a name many aquarists already trust for water care.
• Fits naturally into a reef maintenance routine alongside testing and water changes.

This little 100ml bottle is built for the keeper who likes to make precise, measured moves. When your testing shows phosphorus drifting low, Reef Phosphorus lets you raise it on its own terms, without the dissolved organics Seachem says it leaves out. For anyone caring for corals and macroalgae, that kind of targeted control is reassuring, whether you run a nano tank or simply prefer to dose in smaller amounts. Keep your test kit close, follow the brand's dosing guidance for your tank volume, and let this concentrated supplement help give your reef the steady environment it depends on.