Orca Laboratories Nitra-Guard Bio-Cubes V4 - 500 mL

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This item has been discontinued.

Nitra-Guard BIO-Cubes V4 - 500mL (for aquariums 40-130 gallons)

  • The world’s fastest & most effective carbohydrate based nitrate remover
  • More economical & effective than any other product of it’s kind in the world…nothing can compare!
  • Reduces 50ppm Nitrate to 0ppm within 1 to 2 weeks in Freshwater and Seawater
  • Easy & convenient use, no daily feedings or dosings, just add as directed and enjoy 4 to 6 months Nitrate free water
  • No more Deep Sand Bed Filters required which saves space, time and money
  • 100% natural, biological Nitrate removal, no chemicals or metals like iron or aluminium
  • No effect on pH or alkalinity
  • MASSIVELY Reduces Water Changes
BIO-Cubes are made from 100% biologically degradable polymers that effectively remove both nitrates and phosphates from both marine and freshwater systems. BIO-Cubes have a very high surface area and contains 400% more carbohydrates than any other brand, making it the best product of its kind in the world. Independent testing in real world scenarios, have proven BIO-Cubes to far outperform all other competing products. No other product of its kind can compare with the explosive performance that BIO-Cubes can offer. BIO-Cubes are very versatile and can be used in filter bags, fluidized reactors and denitrators. BIO-Cubes require no maintenance and require no feeding dosages making it the easiest and most convenient nitrate and phosphate removing product on the market. Nitra-Guard BIO-Cubes comes with a free filter bag with every jar (excluding 5000ml size).

How it all works
Bacteria consume the high carbohydrate source found in the BIO-Cubes and form a biomass that absorbs nitrates and phosphates from the water in the aquarium. This biomass is then skimmed out with a protein skimmer or is consumed as a food source by corals and clams.

When culturing bacteria, 2 of the most important factors that will determine the size of the colony are surface area and food source. BIO-Cubes look like small open celled sponges giving the product a massive surface area. BIO-Cubes also has 400% more biologically available, insoluble polymer carbohydrates than any other product in the world. These 2 factors create conditions that are perfect for culturing and sustaining large bacteria colonies required to effectively remove phosphate and nitrate from aquariums. It is these 2 factors that have made Nitra-Guard BIO-Cubes the world’s best carbohydrate based nitrate removing media. Independent tests that were performed in real world scenarios revealed that BIO-Cubes had the ability to reduce nitrates from 60ppm down to 5ppm in under 2 weeks while competing products claim to only start working after 2 weeks!

Directions for use
The amount required will depend on stocking densities and amount of food added to the aquarium. For heavily stocked tanks, use 3ml to every 1liter of aquarium water and for aquariums with lighter stock loads, add 1ml to every 1liter of aquarium water.

The Nitra-Guard BIO-Cubes work best in an oxygen-rich environment with good waterflow. To get the best results, the “Bomb Method” as described in the instructions can be used. The BIO-Cubes can also be used in a media reactor or a filter media bag and placed near the protein skimmer to assist in removing the nitrate/phosphate-rich biomass faster. If using the Nitra-Guard BIO-Cubes in a reactor, make sure the reactor can be fitted with a venturi to provide sufficient oxygenation to the BIO-Cubes. After 1 to 2 weeks, the bacteria colonies will become prolific enough to start lowering nitrate levels in your aquarium. If nitrate and phosphate levels in your aquarium are high, some cloudiness may occur which clears in a few days. Soak BIO-Cubes in freshwater for 24hrs before use.

Available sizes: 250ml / 500ml / 1,000ml / 5,000ml

Product Manuals & Documentation

Orca Laboratories Nitra-Guard Bio-Cubes V4 - 500 mL

Owner's Manual available for download in Adobe PDF file format



Experience Level: Intermediate

Works like a Big Dog

I've been fighting Red Cyano forever and a day in a 29 gal. reef. Tried increased flow, water changes, etc.... Bought a 1000ml bottle of Nitra-Guard Bio-Cubes. I took Fluval 206 canister that I have been using for Boyds chemi pure and Phosphate Out (AquaMaxx) and cut the canister flow back to 40%. I added about 200ml (20%) of the bottle of Nitra-Guard Bio-Cubes in a media bag inside the canister. After 10 days not a speck of Red Cyano. My corals were not adversely affected in anyway.I know this is contrary to the product directions but I am satisfied with the results.

3 out of 3 found this review helpful

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mike fernandez from holbrook, NY UNITED STATES


Experience Level: Intermediate


After 15 years of trying to control nitrates with additives and major water changes in my 100gal FO tank and i have tried them all this product has allowed me to reduce my water changes to 15 gal per month down from 40, nitrates remain under 20 from 80-90. Next month i'll try 10 gal.If nitrates are your problem give this a try.Use as instructed very easy.

1 out of 1 found this review helpful

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Regal Angel from CA


Experience Level: Expert


I am testing Nitra-Guard Bio-Cubes on a 300 gal. Fish Only system. My nitrates were well over 100ppm with weekly 50g water changes. I started with 3 liters of cubes in bombs (bag w/air stone) in the sump. Gradually over a period of several weeks nitrates dropped to about 25ppm where they remained for three weeks. I then utilized a modified pellet reactor for a maximum of 5 liters of cubes. A submersible pump is used for flow at a low rate with multiple air stones at the inlet for saturated water flow with air. In three weeks the nitrate level dropped from 25 to 2-5ppm! No bacterial haze on acrylic viewing panels, no filter plugging, no pellet mulm. Now testing to see how often I need to add cubes to the reactor. Very easy to use and self regulating cubes. (need the Titanium cubes)

4 out of 4 found this review helpful

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Experience Level: Beginner

Effective product

I have a 75 gallon salt tank and my nitrates spiked up to above 80 ppm. I did 50% water changes with no avail. I bought this product and within 1 week my nitrates were down to 5 ppm !! Great and effective product! Definately recommend it and I will buy again the in future!

2 out of 2 found this review helpful

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Experience Level: Intermediate

Life Saver

I've been using this product for about 9 months now. First in a 20 gallon that I could not rid of nitrates, after adding these to the canister filter, I had 0 nitrates and great growth... I was just fighting phosphate / red slime issues... I added NG to a reactor that I had and in 2 days the water was clear, 2 weeks and the corals are growing, the fish are happy, life is goos... nitrates are negligible and since the burns phosphates to kill nitrates, the phosphate problem is gone as well... I can say with absolute certainty that in neither tank did Nitra-Guard ever change my PH in any way. Great product, you need to carry the titanium product.

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Experience Level: Beginner

work on no3 but low on ph

before i using nitra guard my nitrate is:0.50ppn after in 2 day i test(readsea test kit) my nitrate is :0.25ppn.the problem is the bio cube kept my ph down to 7.75.before i use my ph stability :8.2 to 8.4

3 out of 6 found this review helpful

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