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PhosGuard, 4 L / 1 gal.

  • Based on 1,402 reviews
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Availability: 12 left in stock
Fulfilled by Champion Lighting and Supply Co.

Arrives Sep 29 – Oct 1
Order within 14 hours and 16 minutes
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Size: 4 L/ 1 gallon


Features

  • REMOVES SILICATE AND PHOSPHATE: PhosGuard rapidly removes phosphate and silicate from marine and freshwater aquaria.
  • IRREVERSIBLE BINDING: PhosGuard will not release phosphates or silicates back into your tank or aquarium due to its ability to exhibit strong binding capabilities, consequently reducing phosphates and silicates to very low levels.
  • USE: Although PhosGuard is effective in both fresh and marine water, it will provide optimal results in sea water and the need for it is better defined in sea water.
  • DIRECTIONS: Use 85 mL (13 cup) for every 200 L (50 US gallons) saltwater or 400 L (100 US gallons) freshwater. For best results, PhosGuard should be rinsed before use and placed so as to maximize the flow of water through it but not so that it tumbles against itself in flow.

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.


Brand: Seachem


Liquid Volume: 4 Liters


Item Weight: 8.02 Pounds


Item Form: Liquid


Target Species: Fish


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 8 x 8 x 7.5 inches; 8.02 Pounds


Item model number ‏ : ‎ 189


Date First Available ‏ : ‎ October 2, 2001


Manufacturer ‏ : ‎ Seachem Laboratories, Inc.


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sep 29 – Oct 1

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.

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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

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