Seachem Laboratories Reef Nitrogen Supplement 500 mL, 17 oz

If you keep a saltwater reef at home, you already know how much your corals and macroalgae depend on a balanced water chemistry. Seachem Laboratories Reef Nitrogen is a concentrated supplement made to help you manage the nitrogen side of that balance in your reef aquarium. This is the larger 500 mL (17 oz) size, a practical pick for established tanks or busy reef keepers who dose regularly and would rather restock less often.

• Targets nitrogen specifically, so you can support your reef without guessing at a broader cocktail of additives.
• Seachem notes that supplementing inorganic nitrogen provides a targeted means of increasing nitrogen without also adding phosphate.
• The brand explains that maintaining nitrogen levels alongside phosphorous levels matters for the health of corals and macroalgae.
• According to Seachem, balanced nitrogen supports optimal growth and coloration of corals and macroalgae in your display.
• Concentrated formula means a focused approach to dosing for your reef system.
• The 500 mL (17 oz) bottle gives you a generous working supply for ongoing maintenance.
• Made for reef aquaria, so it slots into the routine you already run for your tank.
• Single bottle, ready to add to your reef-care lineup at home.
• From Seachem Laboratories, a familiar name to many aquarium hobbyists.
• A sensible choice for keepers who want to address one variable at a time.

Healthy reefs come from steady, thoughtful care, and nitrogen is one piece of that bigger picture. Always follow the label and dose to your own tank's needs and test results, since every reef is different. Pair Reef Nitrogen with regular water testing so you can keep an eye on how your corals and macroalgae respond over time. For the reef keeper who treats their tank like a tiny ocean worth protecting, this larger 500 mL bottle is an easy way to keep your nitrogen-management routine stocked and ready. Give your corals and macroalgae the attentive care they deserve, one measured dose at a time.