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AZ-NO3 Nitrate Eliminator 240mL


Item #: CP2151

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Fourth Generation Formula:  The NEW AZ-NO3 with it`s new "Cold" filtering and processing techniques reduces the clouding effect in even poorly-maintained (ionically-imbalanced) marine aquariums. Its nitrate-removal ability has sped up 2x as fast as before. In addition, its shelf-life is now close to indefinite when un-opened. Or up to 60 days when opened and stored in refrigerator.

Please Note: For use with saltwater tanks only.


The AZ-NO3 (Absolute Zero - NitratesTM) product works entirely by aerobic Cellular Respiration on the target Nitrate molecule, which is then removed by the Protein Skimmer. The oxidoreductases necessary for these processes are the chemical mechanism of an enzyme action.

In the most simplest of explanations, AZ-NO3 can be considered an essential food, required by the active enzyme maltase that functions as a cellular respirator. The manufacturing process renders this product as an undesirable food to certain detrimental enzyme (amylase and invertase) that could uncontrollably proliferate in the aquarium.

Our product utilizes a specific enzyme in the maltase group to activate the oxidoreductases necessary to reduce nitrates by cellular respiration in the aquarium. The product itself does not contain this enzyme, but can be thought of more like a seed, a seed contains the germ (plant) and the food for the plant to grow. The mature plant then becomes the basic food product utilized.

The active ingredient in our product is Cozymase which functions in the oxidation of proteins and of many other compounds important in the intermediary metabolism and the resulting active enzyme Maltase in the aquarium. The Massecuite is food for both the Cozymase to develop and the resultant Maltase to thrive.


The proper denitrifying dosage of the product is 1/4 ounce, daily, for each 50 to 60 gallons of water in the marine aquarium system, until nitrates are undetectable. Overdosing, (up to double the amount) is preferred to underdosing and is not harmful to livestock. Larger aquariums will require a larger dose, but nitrates are normally reduced to zero within the same time period. Many aquarists inadvertently introduce nitrates on a continuing basis, through water changes, food, additives, etc., therefore requiring that they maintain the enzyme activity at a low maintenance dosage to hold nitrates in check. Initially the maintenance dosage should be 1/2 of the denitrifying dosage, steadily decreasing the amount of AZ-NO3 used until nitrates can be maintained at an undetectable level. The intent is to slowly wean the aquarium off the AZ-NO3 product entirely, allowing the natural denitrification properties of the aquariums live rock and/or plenum to come into full functioning. The maintenance dosage can be rescheduled for bi-weekly or even weekly additions as the live rock or substrate develops to it`s full potential.

Effects AZ-NO3 provides many other benefits besides nitrate reduction. Upon addition of the product to the aquarium, you will notice that the Protein Skimmer becomes more efficient and remains that way for approximately 30 days after the final use of the AZ-NO3. In addition, as the enzymes become active, all sediments and pre-filters in the aquarium remove larger amounts of undesirable organics, thus requiring more frequent filter changing.

  • It does not interfere with any nitrate test kits to give you illusionQ and fake denitrating effects like the other product (See below "Latest Update").
  • It brings down & maintains your nitrate from as high as 100ppm or more to an Absolute-Zero level. Hence the name.
  • Safe for reef and fish-mainly marine systems (saltwater use only). Will not harm your delicate corals.
  • Works with an efficient protein skimmer to export the bonded nitrate compounds. An alternative way is to employ Polyfilter Pads to adsorb the bonded nitrate compounds.
  • Also dramatically enhance the efficiency of your protein skimmer in the removal of other detrimental dissolved organics.
  • Contains absolutely no yeast nor complex sugar which will cause adverse effects & other unpredictable complications upon long term usage.
  • Since that it is not bacterial-based. Its potency will not be affected by any other additives, medications and supplements. It is fully-compatible with any other chemical engineered for aquatic use.
  • Fully-tested by actual hobbyists with all kinds of marine systems and different starting levels of nitrate concentration.
  • Newly copyrighted formula developed by a group of Biochemists / Hydroculturists. Product will last for 1 year at 70 degrees.
Latest Update

The AZ-NO3 may not work to its full effectiveness under the following conditions:
  • UV Sterilizer running near or above 50,000 microwatts - sec/cm2.
  • Ozone saturation above 40% in the protein skimmer.
  • Customer not changing pre-filter pads and/or filter sponges in mechanical filters before natural nitrification breaks the maltase molecule back down into it`s original nitrates. So, clean your pre-filters and all pads frequently please.
  • Under rare situations that should your fish show stress, an Iodine supplement is recommended. Please bare in mind that the AZ-NO3 enhances the efficiency of your skimmer and Iodine may have been exported.
  • Watch your ORP while using this product and increase aeration if there is a need.

4 Stars


Reviewed on
July 03, 2020

Best No3 reducing supplement

I always keep it handy, this is the easiest method of decreasing No3, I am using it since 10+ years not regularly but whenever or if No3 is elevated beyond my required levels. HIGHLY Recommended! Never lost anyhing

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Reviewed on
September 27, 2019

No, I would not recommend this.

it worked

Pros: lowered Nitrates

Cons: Lost fish

used the dosing as recommended on the bottle when I got to the first 2 nights of full dose the tank became cloudy, fish became obviously distressed during this time period and lost 2 chromos, 1 pj cardinal and a damsel Other fish seemed to weather it I am not a couple of weeks past those 2 nights and remaining fish are doing well and nitrates much lower Just not sure benefit was worth the fish loss

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Reviewed on
July 29, 2019

Yes, I would recommend this.

Great Product

Pros: Easy to add. Inexpensive.

Cons: Cloudy water during the first stage. It does dissipate after a couple of days.

I have used it for two weeks already and I saw a drastic change (good one). My Nitrate levels lowered were noticeably lower after day 4. Iodine was reduced as well but I read from other reviews to supplement. Great Product for sure.

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Reviewed on
March 26, 2019

Yes, I would recommend this.

Works very well.

Pros: lowers nitrates safely and well.

Cons: lowers iodine...so, measure and supplement

Excellent product for decreasing nitrates, and keeping them low. I have used it for years. BUT, know your iodine will drop...so, supplement for that.

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Reviewed on
March 11, 2018

Yes, I would recommend this.

Works great

Only thing that has worked for me.

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yama h

Reviewed on
August 30, 2016

Yes, I would recommend this.

AZ-NO3 Review

So far I am 11 days into this and my nitrates have dropped from 50 ppm to about 20 ppm now! I have tried nearly everything (vinegar dosing, less feeding, bi-weekly W/C, and better husbandry overall) to get my nitrates down with no luck. I had recently removed all my sand and believe this lead to an imbalance which caused the nitrate spike. I've noticed less algae growth on my glass and dying off of spots of cyano bacteria. I honestly wasn't sure this would work, but after reading ALL the reviews I decided to make the purchase. My primary reason for dosing this is to get NO3 down and to let my biopellet reactor do the rest of the work! So far I am very pleased with the results and will comment again once nitrates are down to zero! Thank you Marine Depot for carrying this product; I recommend this to anyone looking to lower nitrates! P.S. I gave a 4/5 because I did lose my emerald crab and skunk cleaner shrimp during the 11 days of using this product. Not sure if it has anything to do with it, but they were fine, healthy, and active before...

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gary r

Reviewed on
June 04, 2016

Yes, I would recommend this.

Got Me Out of a Tank Recycle

I have a well-stocked tank, with a fairly high bio-load but still held excellent water parameters for years. Unfortunately, messing around with the sand caused a recycle. I tried my best to avoid chemical solutions but despite my best efforts, my nitrifying bacteria just couldn't catch back up. This was the perfect intermediary to get nitrates down to 0 until my bacteria could reproduce enough to handle things on their own. Thanks for saving my fish!

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intarasak hovichitr

Reviewed on
August 10, 2015

Yes, I would recommend this.


It's work as description and NO3 decreased very fast.

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Reviewed on
April 01, 2015

Yes, I would recommend this.

Excellent Product

I was never able to get my nitrates <20ppm no matter what I tried. Carbon-dosed vinegar for a year which helped a little but created lots of unwanted bacterial growth in my display tank. After 15 days of using AZ-NO3 my nitrates are 0ppm for the first time ever. I'm now dosing 4ml day with an auto doser to keep things in check.

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Reviewed on
December 22, 2014

Yes, I would recommend this.

This stuff WORKS!!

THIS STUFF WORKS! I have had a saltwater tank for 15 years. I've tried lots of other products and techniques to reduce Nitrates to zero! I have 40ppm Nitrate level. I followed the instructions and it lowered the nitrates to zero in 24 days. I run a protein skimmer as it said it is needed for this stuff to work. I have fish, carpet anenome, bulb anenome, many SPS corals and even had clownfish in the process of laying eggs and fish were born into the tank while using this product. Ive tried so many other products that didn't work, this was the first one in years that did!

Was this review helpful? 3 0

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