API FilStar Nitra-Zorb

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This item has been discontinued.

Aquarium Pharmaceuticals, API, MARS Fishcare

Canister filter media designed to fit the FilStar XP. For complete removal of Ammonia, Nitrite and Nitrate from freshwater. Rechargeable pouch.

Nitra-Zorb™ - for fresh water

  • Tested and used by Jack Wattley, world famous discus breeder
  • Removes ammonia, nitrite and nitrate from freshwater aquariums
  • Designed to be used when setting up a new aquarium
  • Ideal when breeding fish orraising sensitive species
  • Protects against sudden ammonia and nitrite "spikes" and "surges" inestablished aquariums
  • Rechargeable
Nitra-Zorb is the first water filtration medium that removes ammonia, nitrite and nitrate in freshwater aquariums. Nitra-Zorb is a blend of natural and synthetic ion-exchange resins that selectively removes ammonia, nitrite and nitrate. Nitra-Zorb, when used in new aquariums, controls the level of toxic ammonia and nitrite during the initial development of the biological filter. In established aquariums, Nitra-Zorb helps control sudden spikes in ammonia and nitrite from the addition of new fish or anytime ammonia or nitrite is detected.

Ammonia and Nitrite in the Aquarium:
  • Tropical fish continuously release ammonia. Urine, solid waste and uneaten fish food also release ammonia as they decompose. Nitrifying bacteria in the biological filter convert toxic ammonia to nitrite (also toxic) and then to relatively harmless nitrate. This process is called the nitrogen cycle. Newly set-up aquariums do not have enough nitrifying bacteria to keep ammonia and nitrite at safe levels. It can take 4 to 6 weeks for the nitrifying bacteria to become established and form an efficient biological filter. It is during these first weeks that most aquarists experience fish loss due to high ammonia and nitrite levels. The diagram shows the ammonia and nitrite levels in new aquariums, both with and without using Nitra-Zorb.
  • Elevated ammonia levels damage the gills of fish, preventing oxygen uptake. Nitrite entering the blood combines with hemoglobin and prevents blood from carrying oxygen, resulting in stress and suffocation. Even very low levels of ammonia or nitrite can cause detrimental metabolic changes, leading to a greater susceptibility to disease. Even in established aquariums, ammonia or nitrite can be a problem. Each time a new fish is added to an aquarium, the biological filter must adjust to the higher level of waste being produced. When medications and remedies are used, the biological filter is often disrupted. Under these conditions, ammonia and nitrite can reach harmful levels.
Nitrate in the Aquarium: Scientific research has shown that nitrate is relatively harmless to freshwater fish. However, many breeders of tropical fish feel that low nitrate levels are "more natural" and, therefore, better for tropical fish. Nitrate has also been shown to negatively affect the uptake of nutrients from food. Nitra-Zorb will reduce nitrate and promote a more natural balance in the aquarium.

Nitrate Removal: Nitra-Zorb is excellent for continually scavenging nitrate from freshwater systems. Keep in mind that many water supplies contain nitrate. Test tap water used in the aquarium for nitrate. Many aquariums may contain over 300 ppm of nitrate and will require a week or longer to lower nitrate levels. Recharge Nitra-Zorb every 5 days until nitrate is reduced to 20 ppm or less. Then, recharge Nitra-Zorb every 2 weeks, or when nitrate levels exceed 20 ppm.

Directions for use in RENA® FilStar Filters:
  • Remove Nitra-Zorb pouch from plastic bag.
  • DO NOT open Nitra-Zorb pouch. One 210 g pouch should be used for every 55 U.S. gallons (208 L) of aquarium water.
  • Rinse Nitra-Zorb pouch under tap water to remove any dust.
  • Place filter pouch directly in FilStar filtration basket after (above) filter foams.
  • Recharge filter pouch every 5 days until safe nitrate levels are reached. Then, recharge every 2 weeks to maintain best performance.
  • Replace pouch every 1 to 3 months, depending on stocking density and water quality.
Use Aquarium Pharmaceuticals Test Kits to monitor water quality weekly. Nitra-Zorb is designed for use with all Filstar filtration media.

Recharging Nitra-Zorb: Nitra-Zorb can be easily recharged in a warm salt solution. Dissolve 80 g (4 tablespoonfuls) of non-iodized salt in 240 ml (8 ounces) of warm tap water (approximately 48°C/120°F), soak the pouch for at least 2 hours and rinse lightly in tap water before re-use. Nitra-Zorb resins will gradually become fouled with organic matter, and therefore Nitra-Zorb should be replaced when performance declines.

Product Manuals & Documentation

API FilStar Nitra-Zorb

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

Manufacturer Info

Aquarium Pharmaceuticals Aquarium Supplies
Aquarium Pharmaceuticals (API) has been helping people take good care of ornamental fish for over 40 years. Their research and development scientists have advanced the care of fish with all-natural medications, stable bacteria for biological filtration, one-bottle test kits, consumer-friendly dosing caps and much more. They’ve received over 25 global patents for their breakthrough innovations in the aquatics industry. And they continue to look for ways to improve the fishkeeping experience for hobbyists. Research. Experience. Dedication to scientific, quality treatment for healthy fish. It’s what makes API the first choice of aquarium owners. API manufactures and sells hundreds of products across many different product categories, including aquarium and pond treatments, aquarium equipment, aquariums and fish nutrition.



Experience Level: Intermediate

nitrite reduction

Just started up a 55 gallon reef tank, the nitrite level after 8 days was 1.5 ppm. I removed the filters from a marineland 200 power filter and droped in the nitra Zorb packet, less than 24 hours later my reading was zero. I would suggest to anyone starting a new tank, to have this product on had, great stuff.

7 out of 8 found this review helpful

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Experience Level: Intermediate

Works great!

Last year, I switched over to a Rena Filstar XP3 canister filter for my fishtank. My tank contained at the time 1 goldfish and 1 pleco. Shortly after I bought the filter (giving it time to cycle with the tank), I had moved the fish into a 90 gallon tank from the 29 it had been in, and added 2 more goldfish once the new tank had cycled. This canister filter, and using NitraZorb in it, have made all the difference to me! Prior to using these products, I would have to perform daily water changes and constantly check the pH/ammonia/nitrite/nitrate levels in the tank because the old filtration wasn't keeping up with my messy, huge fish. Now, I perform a much more normal water change and filter cleaning schedule and the tank stays nice and stable. My enormous fish and I are very pleased with how clean the tank stays, and having the Nitra-Zorb in the tank is just the ticket for ensuring that my fish will remain healthy!

3 out of 3 found this review helpful

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