The 8 Best Saltwater Aquarium Nitrate Reducing Products of 2020

Saltwater Aquarium

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It has been reported that high aquarium nitrate levels can cause a variety of issues for your fish, including stress, lower immunity, decreased the ability to reproduce, and algae growth. Excess nitrates (NO3) in a reef aquarium can be detrimental to the health of corals and many other invertebrates.

Aside from using a denitrator unit, many methods (i.e., the Vodka Method or macroalgae in the refugium) and materials can be utilized to absorb or convert nitrate to a harmless substance (nitrogen gas). Here are some nitrate absorbing products which will help resolve high nitrate problems in saltwater aquarium and reef tank systems.

  • 01 of 08


    Manufactured by SeaChem, De-Nitrate removes nitrates, nitrites, and ammonia. This product comes in loose form and must be contained in a mesh bag or a filter chamber and placed in the water stream.

  • 02 of 08

    API Nitra-Zorb

    This is a blend of natural and synthetic ion-exchange resins that selectively remove ammonia, nitrite, and nitrate. In new aquariums, Nitra-Zorb controls the level of toxic ammonia and nitrite during the initial development of the biological filter. In established aquariums, it helps control sudden surges in ammonia and nitrite caused by the addition of new fish or anytime ammonia or nitrite is detected.

  • 03 of 08

    Instant Ocean Natural Nitrate Reducer

    Instant Ocean Natural Nitrate Reducer is the easy solution for long-term reduction and control of aquarium nitrate levels. The patented formula promotes the natural denitrification process of converting nitrate into nitrogen gas.

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    Poly-Filter Pad

    With the Poly-Bio Filter Pad by Poly-Bio-Marine, Inc., water impurities such as phosphate, nitrate, copper, silicate, and even ammonia are absorbed. The pads can be regenerated by simple rinsing in saltwater (saltwater use can be regenerated by the reverse, rinsing in freshwater). Simply roll or cut the pad to any shape, place it inside a canister filter or incorporate it into any type filtration system to easily remove troublesome elements in saltwater aquariums.

    Continue to 5 of 8 below.
  • 05 of 08


    Purigen is a synthetic adsorbent, not a mixture of ion exchangers or adsorbents, but a unique macro-porous synthetic polymer that removes soluble and insoluble impurities from water. Purigen removes proteins, nitrites and nitrates, ammonia, and a broad spectrum of organics. Purigen darkens progressively as it exhausts, and is easily renewed by treating with household bleach.

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    Acurel Nitrate Reducing Pad

    Acurel Nitrate Reducing Pad is a rigid gray polyfiber pad infused with a fast-acting nitrate reducer which reduces nitrate levels in aquarium water. The 1/2-inch-thick pad traps free-floating debris while reducing and maintaining nitrates levels. The large pad surface area also acts as a biological filter base that promotes beneficial bacteria colonies. Simply cut the Acurel Nitrate Reducing Pad to fit any hang-on aquarium filters, canister filters, internal filters, and wet/dry filters.

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    Red Sea NO3:PO4-X Biological Nitrate and Phosphate Reducer

    Red Sea NO3: PO4-X Biological Nitrate and Phosphate Reducer is a liquid form of carbon which stimulates certain species of natural bacteria that convert nitrate into nitrogen gas. A good protein skimmer should be used in the aquarium system when using this product to collect the excess bacteria and byproducts which will be formed.

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    DrTim's Aquatics Bashsea Pellet Master

    DrTim's Aquatics Bashsea Pellet Master is a heavy-duty acrylic media reactor perfect which utilizes NP-Active Pearls to remove both nitrates and phosphates from your aquarium water. The large reaction chamber is designed to handle a high media volume. The non-clogging design provides even water flow to tumble media gently for maximum media-water contact.

    The Reactor Kits are available in three sizes and include everything (including pumps and plumbing material) needed to set up and operate.

    • PM-I Reactor Kit: For aquariums systems up to 75 gallons.
    • PM-II Reactor Kit: For aquarium systems up to 150 gallons.
    • PM-III Reactor Kit: For aquarium systems up to 300 gallons.