Great Aquariums Start Here
Live Chat Support
    Free Shipping
  • FREE Shipping ON $75+
  • 14-Day Low Price Guarantee
  • Low Price Guarantee
  • Same Day Shipping
  • Same Day Shipping
99% of items we carry qualify for FREE SHIPPING in the contiguous United States if you spend $75 or more. Learn More
If you find a product we sell for a lower price at another online store, we will match their price to ensure you always pay the lowest amount when you shop with us. Learn More
Same Day Shipping
We promise to ship your order as fast as humanly possible. In fact, 99% of orders placed before 2 pm EST ship the same day! Learn More
Home » Saltwater Aquarium Supplies  » Filters  » Replacement Cartridges  » For Canister Filters  »  API FilStar Phos-Zorb
API FilStar Phos-Zorb

API FilStar Phos-Zorb

Average Rating 5 2
Write A Review
Product Review
We value your opinion & experience
Thank you for taking the time to review our products!

This is a Product Review for: API FilStar Phos-Zorb
Name to display on the review:
Location (ex: Anaheim, CA):
Your experience level:
How would you rate this product?
Review Title:
Write your review:
(Please focus on product quality and performance)
This item has been discontinued
Item #:
Notify Me
Just enter your email address below and we'll let you know when the product you are looking for becomes available!

Item Code:
Your Email:
Add to Cart or Notify Me
This item is temporarily unavailable but will be back in stock soon.

Item #
Click the Add To Cart button below if you'd like to reserve this item today. Any other items included in your order will be immediately processed and shipped. We will ship this item separately as soon as it arrives. We will not charge you for this item until it ships and you will incur no additional shipping charges.
Enter your email address in the field below and click the Notify Me button if you'd like us to send you an email when this item becomes available. Although you will be immediately notified when we have stock on hand, we will not reserve any units for you; you must return to our website and place an order.

Add to Wishlist
Select Wish List:
Comments (up to 200 characters):
Quantity Desired:
Quantity Received:
Marine Depot 60-day Returns
At Marine Depot, we stand behind our products. That is why we offer a 60-day return period: one of the best in the industry! Learn More

API FilStar Phos-Zorb Information

Canister filter media designed to fit the FilStar XP. For removal of Phosphate from fresh and saltwater.

Phos-Zorb™ - for fresh and salt water:
  • Removes phosphate and silicate
  • Removes phosphate, a by-product of fish metabolism and decaying organic matter and an additive in some tap water supplies, aquarium products and filtration media
  • Will not remove trace elements
  • Will not affect pH
Phos-Zorb is a special filtration material that selectively removes phosphate and silicate, common nutrients found in fresh and saltwater aquariums. In saltwater aquariums, excess phosphate lowers the available calcium and magnesium necessary for the growth of hard corals and other invertebrates.

Sources of Phosphate and Silicate in the Aquarium:
  • There are several natural and "man-made" sources of phosphate. Both well and municipal water supplies may contain phosphate, due to natural weathering of phosphate-containing minerals. Some municipal water treatment facilities add phosphate-containing chemicals to the water supply. Runoff also adds phosphate fertilizers to water supplies. Some phosphate-leaching sources in the aquarium include decaying organic matter, fish foods and products that are added to the aquarium, such as pH adjusters, water conditioners and some brands of activated carbon. If left to accumulate, phosphate can lead to reduced water quality.
  • Silicate enters groundwater naturally through the weathering of mineral deposits. Additionally, sodium silicate is added to tap water by some municipal treatment plants to reduce the corrosion of pipes.
Directions for use in RENA® FilStar Filters:
  • Remove Phos-Zorb filter pouch from plastic bag.
  • DO NOT open Phos-Zorb filter pouch. One 150 g pouch should be used for every 55 U.S. gallons (208 L) of aquarium water.
  • Place filter pouch directly in FilStar filtration basket after (above) the filter foams.
  • Rinse basket under tap water for several minutes to remove dust and activate Phos-Zorb. The activation process will temporarily generate some heat in the Phos-Zorb filter pouch.
  • Replace filter pouch every 1 to 3 months, depending on stocking density and water quality.
Use Aquarium Pharmaceuticals Test Kits to monitor water quality weekly. Phos-Zorb is designed for use with all Filstar filtration media.

Phos-Zorb should be replaced every 1 to 3 months to ensure continuous removal of phosphate and silicate. The level of these nutrients depends on stocking density, feeding rate, aquarium maintenance schedule and the nutrient levels present in the source water used in the aquarium. Phos-Zorb is often used continually to keep phosphate and silicate levels under control.

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.

API FilStar Phos-Zorb Reviews

Average Rating
(2 reviews)
Sort Reviews By:

Filstar Phos-Zorb

Reviewers Rating Excellent!

Posted: 11/10/2013 from GREENVILLE, SC UNITED STATES
5.0 5
Experience Level: Expert

Comments: It helped my water to become crystal clear.

Did you find this review helpful? Yes No

Very Pleased

Reviewers Rating Excellent!

Posted: 9/17/2008 from GREENEVILLE, TN UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I have utilized the Phos-Zorb for approximately three weeks and have been very pleased with the results. My objective in using this product was to eliminate pontential algae growth in my 120 gallon tank, maintaining a clean and crystal clear tank. Further more, the pouch (I used two) is very convenient and fits well into my Rena XP4 Filter. I have experienced zero algae growth, and would highly recommend Phos-Zorb as a preventive aid.

2 of 2 People found this review helpful, did you? Yes No

WIN A MEDIA REACTOR! Sign up for hot deals, helpful videos, and a chance to win an Accel Aquatics FR-30 Media Reactor!