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  » Filter Media  » Chemical  » Phosphate Removers  »  PURA PhosLock GFO Phosphate Removal Media - 150 gram
PURA PhosLock GFO Phosphate Removal Media -  150 gram

PURA PhosLock GFO Phosphate Removal Media - 150 gram

Average Rating 4.5 18
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: PURA PhosLock GFO Phosphate Removal Media
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)
In Stock: Order by 2PM EST for same-day shipping (M-F)
This item is in stock in our East and West Coast warehouses
Item #:
MSRP: $14.95
You Save: $2.96 (19%)
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
Add to Wishlist
Select Wish List:
Comments (up to 200 characters):
Quantity Desired:
Quantity Received:
FREE Shipping Promo offers FREE standard ground shipping via UPS on orders of $75 or more for orders containing non-overweight or oversize items (orders which do not qualify for our FREE shipping promotion will still be shipped at a discounted rate).

Terms and Exclusions:
  • Offer valid only on orders shipping within the contiguous United States. Orders shipping to Alaska, Hawaii, Puerto Rico, Guam or other US Territories do not qualify for this promotion.

  • This promotion does not apply to items requiring expedited shipping, such as refrigerated products, frozen products or live rock.

  •'s FREE shipping promotion does not include products sent in oversized or particularly heavy boxes. This may include but is not limited to aquariums, canopies, chillers, external water pumps, metal halide magnetic ballasts, stands and substrate/sand. These items may be subject to additional shipping handling charges. Should shipping surcharges apply, they will be noted on individual product pages and / or displayed during check-out. We will, however, pay a portion of the shipping charges for these orders.

  • Shipping surcharges, such as special handling are NOT covered under the FREE shipping promotion.

  • Shipping charges for returned merchandise is non-refundable. Please read's Return PolicyPolicy for more information.

  • Price matched (Low Price Guarantee) or discounted orders do NOT qualify for our free shipping promotion.
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.

Enter the price, shipping cost and website address where you found the lower price. Then click the "Add to Cart" button. We will review the lower price while processing your order and make any necessary reductions before your order ships. Some restrictions apply. See Terms & Conditions.
Shipping Cost*
Competitor's Website*
*Required information
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

PURA PhosLock GFO Phosphate Removal Media - 150 gram Information

Groundbreaking filtration media at the right price. For Reef, Marine, Planted, and Fresh Water aquaria!

The PURA family of filtration media is formulated to reduce scum formation in fresh and marine aquaria.

All PURA products are formulated with Beta-GFH (Beta Ferric Oxide Hydroxide), the groundbreaking German made phosphate removing media that eliminates the primary nutrient of aquarium scum. PURA filtration products lead to a much cleaner and less labor-intensive aquarium, good for the animals, good for the hobbyist, good for customer retention.

Hydrated Beta-GFH is vastly superior to white colored Alumina based phosphate removers and greatly superior to numerous Alpha-Ferric Hydroxides sold in dry form.

PURA PhosLock removes 45% more phosphates than Alumina media, and 20% more than Alpha-Ferric Hydroxides. Unlike Alumina, PhosLock never leaches phosphates back to the aquarium. Unlike competing Alpha-Ferric Hydroxides, PhosLock never disintegrates and never turns soft and muddy in aquarium water. PhosLock comes fully activated right out of the jar. PhosLock does not need a specialized reactor and can be easily confined and implemented in a fine meshed media bag.

PURA PhosLock
Professional Strength Phosphate Remover

PURA PhosLock is 100% pure Beta-GFH and will keep phosphate levels at 0 ppm, a highly desirable level in reef, planted, and exhibit quality aquaria. This is the most cost effective phosphate remover in the market place and unlike dry phosphate removers, PhosLock does not turn to mush in an aquarium. PhosLock outperforms all competing products. Packed hydrated with an induction welded foil seal for freshness, protection, and long shelf life.

PhosLock is the benchmark German made ferric hydroxide media for total phosphate removal in all aquaria. Used all over the world, it is the product of choice for many critical water purity applications. PhosLock permanently binds phosphates. With regular use of PhosLock any aquarium fresh or salt, reef or planted, will stay much cleaner and less maintenance labor intensive! Media bag with PhosLock can be placed inside of: canister filters, power filters, pond filters, sumps, refugiums, corner filters, next to uplift tube on UG filter plate. PhosLock can be placed directly into Bio-Bags or other fine floss bags. PhosLock is 5 to 10 times more effective than white activated alumna media and it is completely safe for fish and invertebrate, fresh and salt-water aquariums.

Reef Chemistry Calculator
Use our chemistry calculator to find out how much you need to add to your aquarium.

Manufacturer Info

Magnavore Company
Magnavore Company started manufacturing magnetic algae cleaners in 1998. They quickly developed a reputation for a high quality effective product. Today they manufacture the third generation of premium Magnavore magnets with innovations like Extended Reach, Glasscare and Acrylicare Brushes, Tune-Up and Acrylicare kits. In 2004, they began manufacturing new filtration products that are a cut above the rest! Each product made is the best in it`s category. That Magnavore`s our focus and promise.

PURA PhosLock GFO Phosphate Removal Media - 150 gram Reviews

Average Rating
(18 reviews)
Sort Reviews By:
of 2

Seems to work ok

Reviewers Rating Average

Posted: 3/19/2014 from LOUISVILLE, KY UNITED STATES
3.0 5
Experience Level: Expert

Comments: Better than other products.... The directions are not good and make sure to buy the huge tub of it. Ur changing it every 3 months in a reactor.

Did you find this review helpful? Yes No

Very Poor Product

Reviewers Rating Unsatisfactory

Posted: 4/13/2013 from FREDERICK, MD UNITED STATES
0.5 5
Experience Level: Intermediate

Comments: At first I was mystified as to why this product was getting 5 stars. After reading a few I realized most folks were using GFO for the first time & were overjoyed to see results with their algae problems. Yes, Pura Phospock works as do all the other major brands. I've used a bunch of different brands & this is by far the worst. I bought the 150 gram package. I didn't weigh it but the volume was exactly one half of the same 150 gram package of Two Little Fishies Phosban product! Very evident looking at the reactor. Got out a magnification glass & say irregular granual size. It does not "dance' properly like other products. The worse thing is the DUST! The TLF Phosban rinses clean with very little water. I used 4 gallons of RODI water rinsing & it still ran red. Unacceptable for a premium priced product! The only good thing is they include a very nice Velcro media bag which I don't use for GFO but will use for carbon. Don't be impressed with this "German made alpha ferric oxide" marketing jibber jabber. That's all marketing hype IMO. THE STUFF DOES WORK BUT THERE ARE BETTER PRODUCTS ON THE MARKET. I must say their other products have performed very well for me but this was a big disappointment.

4 of 8 People found this review helpful, did you? Yes No


Reviewers Rating Great

Posted: 8/7/2012 from HARVEY, LA UNITED STATES
3.5 5
Experience Level: Intermediate


Did you find this review helpful? Yes No

So far, so good

Reviewers Rating Excellent!

Posted: 3/16/2012 from PORT NECHES, TX UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I have used this product now for about 2 weeks and so far, I have noticed almost undetectable phosphate levels. I have tried many other items up until now. It comes with its own media bag and I just added it to my sump. It doesn't leach the phosphates back into the system like some other products do. My corals also seem to like it.

Did you find this review helpful? Yes No

Eliminates hair algae

Reviewers Rating Excellent!

Posted: 12/19/2011 from Delaware, USA
5.0 5
Experience Level: Intermediate

Comments: Had been battling severe hair algae in my planted aquarium for almost two months. Tried all sorts of remedies recommended by others in forums and such. Phosphate level was 0.09ppm, the rest of the tank chemistry was nominal. Finally bought the small bottle of Pura PhosLock to give it a try and put three tablespoons in a fine meshed media bag of the filter for my 33 gallon tank. In a week the hair algae was reduced and in 3 weeks it was gone. The product is put in a cloth media bag (supplied in the PhosLock bottle) inside the filter - don't miss the step of washing the material in the bag before using it as it is really loaded with fine brown dust. A week ago I noticed the hair algae starting to come back which was a sign the PhosLock needed to be replaced. As the filter needed cleaning I cleaned the filter and replaced the PhosLock and I see the algae being eliminated. It hasn't killed any of my fish or shrimp in the tank. I don't consider it "inexpensive" but considering the time I had been spending brushing algae from the planted aquarium plants, scraping glass, etc, all of that has been greatly eliminated or reduced with PhosLock. In my application it was the solution I'd been looking for. I just bought the largest bottle they sell and this review is a result of that purchase. If you have hair algae issues, especially in a planted freshwater aquarium, I'd suggest trying the small container of PhosLock.

3 of 3 People found this review helpful, did you? Yes No

PURA Phoslock Excellent

Reviewers Rating Excellent!

Posted: 9/18/2011 from Paris, TN UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I really like the way this works in my display tank (150 Reef) I use in in a MR1 Reactor and run it constantly. It will not turn to mush and the grain size is large enough that it's not getting out of the Reactor. I do need to rinse it well first and at times the water will turn a little brown but that filters out within an hour. The fact that it will not release phosphate back into the system (as claimed) is important to me and my Phosphate levels are easily controlled with PURA Phoslock.

1 of 1 People found this review helpful, did you? Yes No


Reviewers Rating Excellent!

Posted: 7/30/2011 from CHATTANOOGA, TN UNITED STATES
4.5 5
Experience Level: Intermediate

Comments: This is wonderful stuff! It dramatically reduced my phosphates from .5 to .1 within a few hours, and at a much lower price than RowaPhos(my previous favorite). And, I am no longer obsessed by that hair algae!

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


Reviewers Rating Excellent!

Posted: 1/8/2011 from CHESHIRE, MA UNITED STATES
5.0 5
Experience Level: Beginner

Comments: just started using PURA PhosLock on my 90G 0ppm what more can I say. Not to mention the great price.

Did you find this review helpful? Yes No


Reviewers Rating Great

Posted: 11/17/2010
4.0 5
Experience Level: Intermediate

Comments: Considerable rinsing but worth the phosphate capacity.

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

Algae galor

Reviewers Rating Excellent!

Posted: 6/19/2010 from EL PASO, TX UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I had algae growing all over everything, glas, rocks, and even the snails were developing hair algae. I used to use Phosphate beads, but it was a loosing battle. I changed bulbs, salt, and gravel. My wife had enough, and it looked like the end of my hobby. Within two weeks, everything started to clear up, along with agressive water changes. I used this product along with a bag of Chemi-Pure, and like magic my reef aquarium is saved.

5 of 6 People found this review helpful, did you? Yes No

of 2
Please make a selection 
WIN A MEDIA REACTOR! Sign up for hot deals, helpful videos, and a chance to win an Accel Aquatics FR-30 Media Reactor!