Seachem Laboratories Reef Potassium Supplement 500 mL, 17 oz

Your corals and macroalgae work hard to grow, and Seachem Laboratories Reef Potassium Supplement in the 500ml (17 oz) size helps you give them one of the building blocks they need. This concentrated supplement is made to raise potassium in a targeted way, so you can support your reef without complicating the rest of your water chemistry. For the hobbyist who likes a focused, no-nonsense addition to the dosing lineup, this larger bottle is a smart, long-running fit that keeps pace with a busy tank.

• Targets potassium, which Seachem describes as an essential element required in metabolic processes, protein synthesis, and the growth of corals and macroalgae.
• Provides a targeted means of increasing potassium concentrations, so you can address this one parameter directly and on purpose.
• Raises potassium effectively without also adding phosphate or dissolved organics, keeping unwanted inputs out of your tank.
• Is concentrated, so each focused dose goes straight toward what your reef actually needs.
• Comes in the larger 500ml (17 oz) size, a practical choice for bigger systems or for more frequent dosing.
• Supports both corals and macroalgae, making it useful across a planted or mixed reef setup.
• Fits cleanly into a measured supplementation routine alongside your other reef care products.
• Helps you keep potassium in range as your corals and macroalgae steadily draw it down over time.
• Comes from Seachem Laboratories, a familiar name in aquarium water care.
• Lets you dial in a single parameter without disturbing the balance of the rest of your chemistry.

When you are caring for a growing reef, having a targeted potassium supplement on hand makes it easy to support the metabolism and growth Seachem describes. This 500ml bottle gives you plenty of room to dose regularly, so you can keep potassium where your corals and macroalgae want it and watch your reef fill in and flourish over time. It is an easy habit to keep once it becomes part of your weekly routine, and the larger size means you reorder less often and always have a focused potassium dose ready when your growing reef calls for it.