Search  for anything...

PhosGuard, 2 L / 67.6 oz.

  • Based on 1,402 reviews
Condition: New
Checking for product changes

Buy Now, Pay Later


As low as $8 / mo
  • – 4-month term
  • – No impact on credit
  • – Instant approval decision
  • – Secure and straightforward checkout

Ready to go? Add this product to your cart and select a plan during checkout. Payment plans are offered through our trusted finance partners Klarna, PayTomorrow, Affirm, Afterpay, Apple Pay, and PayPal. No-credit-needed leasing options through Acima may also be available at checkout.

Learn more about financing & leasing here.

Selected Option

Free shipping on this product

This item is eligible for return within 30 days of receipt

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

To initiate a return, please visit our Returns Center.

View our full returns policy here.


Availability: In Stock.
Fulfilled by Amazon

Arrives Saturday, Nov 23
Order within 20 hours and 38 minutes
Available payment plans shown during checkout

Size: 2 L/ 67.6 oz.


Features

  • For marine and freshwater
  • Rapidly hydrodynamics
  • Removes phosphate

Description

Phosguard rapidly removes phosphate and silicate from marine and freshwater aquaria. It is not recommended for phosphate buffered freshwater. Phosguard is highly porous for high capacity and bead-shaped for optimum water flow. It outperforms all competing products.


Brand: Seachem


Liquid Volume: 2 Liters


Item Weight: 3.66 Pounds


Item Form: Powder


Target Species: Fish


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 4.94 x 4.94 x 4.62 inches; 3.66 Pounds


Item model number ‏ : ‎ 188


Department ‏ : ‎ Home


Date First Available ‏ : ‎ October 2, 2001


Manufacturer ‏ : ‎ Seachem Laboratories, Inc.


Country of Origin ‏ : ‎ USA


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Nov 23

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • First time user
Size: 4 L/ 1 gallon
I only received this product last week of this review request. It rinsed off residue quickly. Seems like water flow through the reactor canister is freely. So far, I accept the results in its action, but need couple weeks more w/water testing.
Reviewed in the United States on July 6, 2023 by Rick889764

  • WARNING can kill your fish/inverts.
Size: 2 L/ 67.6 oz.
Product works! however this is my fault, but I wanted to warn fellow fish keepers. I was noticing a small amount of hair algae in my reef tank. So I decided to add phosguard in a mesh pouch and add it to my refugium. I didn't measure it thinking it didn't matter. I just poured 1cup of it into the mesh bag. Well we ran some errands and when i came back within 2 hours time all the fish were laying at the bottom and gasping for air. I put them all in a hospital tank and they all survived. I did a 30% water change and everything is back to normal. So be careful. ... show more
Reviewed in the United States on February 24, 2023 by Michael F.

  • Works so well!!
Size: 250 mL
I was Dealing with brown algae after only one day of using this my tank was extremely clear and i havent seen any brown algae yet! I would Highly recommend this i love seachem!
Reviewed in the United States on May 14, 2023 by Octavius

  • Really works well
Size: 250 mL
This will be an updated review as I just got the product last night. I have a 20 gallon tank and have been frustrated with how quickly algae seems to be growing on my 'fake' plants in the tank.. I have an algae eater but he can't get all the leaves due to their shape and size. Having phosphate test kit for the pool I decided to check the fish tank. The high mark is dark blue. I've never seen the test water such a dark blue color and I have problems with the pool in the summer due to trees overhead and the Florida climate. My fish tank water had even more phosphates than the pool ever had. So I bought this product after seeing a video on its use. I have an AquaClear 30 filter which uses the foam, purigen, biomedia stages. I took out the biomedia bag and put it beneath the intake and replaced it with the same sized bag filled with PhosGuard. It was roughly half the 250ml container I purchased here. I put it in last night around 6pm (after rinsing it well as directed) and left it. I tested the water today around 3pm and the test water was almost clear, indicating little to no phosphates in the water. It was still a little blue but nowhere near the dark blue prior to using the product. They say to wait 4 days to test the water. I'm thinking by tomorrow the test water will be clear, indicating no phosphates. I expected this result from the reviews I've read and the video I saw, but what surprised me the most was that the algae is disappearing! There are only patches of it left on the leaves and a big patch on my 3 inch round/flat bubbler. I should have taken a before picture of the algae but take my word for it. Just like the guy in the video, I had the result the following day of dying algae. It simply doesn't have anything to eat to stay alive.. and we keep the tank light on probably longer than recommended also. I'll report back in a few days on the final results but so far it's working beautifully. I was expecting to have to take all the plants out of the tank for the typical bleach soak. (i'm careful to soak them in prime or safe to neutralize any bleach before re-using). I never expected the algae to just die off. So far i'm impressed. Also I'm convinced now for this coming pool season about using PhosFree in our sand filter to control Phosphates in the pool. But that's another review. Updates to come. ... show more
Reviewed in the United States on December 24, 2014 by nysnowbird92

  • Algae killer for me!
Size: 250 mL
I have 29 gallon tank, with 7 or so Amazon Sword plants, gravel substrate and tap water (with Prime conditioner to remove Chlorine). The tank is not over stocked. There is about 20 inches of total fish in there between some mollies, guppies and platies. After cleaning the walls and substrate, every 4th day or so brown algae was visible all over the tank. I read online and a slew of things came up for the cause of brown algae - 1. New Aquarium - My Aquarium has been fully cycled for a few months so I skipped this. 2. High Nitrates - I measured this and it was constantly around 20-30 and I would like to keep it that way for plants. I know changing water is important but I would like to do it every 2-4 weeks and not ever 4th day which is crazy! It wasn't around 80-100 nitrates so I didn't want to do anything here. 3. High Light - My light is only on 6-7 hours a day and that is needed for plants so I didn't want to change anything there. 4. High Silicates - I didn't have a Silicate test kit and didn't want to buy one. Neither did I want to change to RO or store bought water. I don't have sand substrate which some sites claimed to be the cause of silicates. So, with process of elimination I decided to get this to remove Silicates from the water as opposed to buying a Algae killer product which may be temporary or have more side effects. Cleaned the walls and vacuumed substrate for one more time, put 3-4 teaspoons in my filter bag and it has been 8 days and no sign of Algae. Fish and Plants have not been affected in any way and are happy! I am thinking once the silicates are removed, I don't have to put more of this in my filter. I can run a 5 gallon bucket of tap water through this 4-5 times during my water change every 3 weeks before refilling my tank. We will see if that works. ... show more
Reviewed in the United States on September 1, 2017 by Mr Yoda

  • Won't buy again
Size: 250 mL
I fought high phosphates for months with this.. I couldn't figure it out. I know I initially got high phosphates from my tap water.. well over 10ppm.. but then I started using RO. Things should have gotten better with each water change. My ammonia and nitrites are zero, my nitrates were less than 5ppm. I'm not over stocked or over feeding. The aquarium is planted. I finally caved and went back to clearmax.. a week later I am finally .5ppm. No more phosguard. ... show more
Reviewed in the United States on June 27, 2023 by V.J.P

  • Go away brown Algae
Size: 2 L/ 67.6 oz.
My tank no longer has a brown algae problem.
Reviewed in the United States on February 13, 2023 by John Sinibaldi

Can't find a product?

Find it on Amazon first, then paste the link below.