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โก Clear water, zero algaeโyour tankโs new secret weapon!
Seachem PhosGuard 250ml is a premium aquarium water treatment that rapidly removes phosphates and silicates from both marine and freshwater tanks. Its bead-shaped, highly porous granules maximize water flow and filtration capacity, effectively starving algae and improving water clarity. Trusted by thousands of aquarists, PhosGuard outperforms competitors to maintain pristine aquatic environments.
| Customer Reviews | 4.5 4.5 out of 5 stars (1,672) |
J**E
Worked great
Had a good amount of brown algae popping up. Tank is about 3 months old now so its to be expected. A corner also gets hit with direct sunlight, which is where it shows most. After about 2 weeks changing this as directed, it cut down on it drastically. Theres still a bit of it, but definitely nowhere near as noticeable as it was prior. I stopped using it and it began to comeback, so I began redosing. But I expect the same results. Definitely recommend buying the large jug seeing as these beads fill every 4 days. It took 2 weeks for a change in a 75 gallon, for reference. I would prefer a purigen like solution for this that's rechargeable. But it did what it's supposed to, and I'm happy enough with that. Seachem always dropping bangers.
N**2
Really works well
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.
D**W
Fish tanks need this!
Great product
R**Y
Product container was NOT checked for Tight Lid or was Shipped Rough
Phosguard works very well for lowering phosphates regarding the aquarium hobby, no problem there. HOWEVER, my shipment delivered today from Amazon had the lid off with little white beads of product all over the outer box it was dropped off in. The manufacturer, Seachem, is partly to blame here as they are NOT using a secondary adhesive held plastic can opening seal. Then Amazon is at fault for shipping not double checking the screw on lid and/or being too rough during delivery.
A**O
Excelente
Muy bien
T**T
OK
OK
M**A
Algae killer for me!
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.
D**I
Effective Band aid (temporary) fix for diatoms
If you have brown algae, this is an effective band-aid (temporary) fix for decreasing silicates In 4 days and using the exact dosage, the seachem phosgaurd dropped silicates from 3.9 ppm to 0.7ppm. For a 20 gallon tank, It takes 3-4 for me to observe a drop in silicates and i notice the diatoms do not grow as quickly. Unfortunately it does NOT completely stop or reverse brown algae growth. It just slows down the growth. This is especially true if you are topping off water or doing a water change. When adding water that is KNOWN to have silicates (seachem multitest kit), you are just feeding and helping the diatoms to grow faster. **As such , you have to periodically remove and replace the seachem phosgaurd regularly as you reach the capacity of the phosgard to hold/bind to silicates. THIS CAN GET COSTLY AND REQUIRE ADDITIONAL MAINTENANCE. Per the instructions, You know you have reached the capacity of the media when your test kit shows the phosgaurd can no longer keep the silicates below a certain concentration (you start seeing silicate concentration creep back up). **overall: it is very effective but temporary and requires additional maintenance to solving your diatom problem. Instead you can try changing your water supply if it has silicates / decrease light intensity and duration/ add a clean up crew that eats algae/ or add more plants to outcompete and thereby starve the diatoms.
Y**O
Perfecta
Buen producto
C**N
Seachem PhosGuard
Seachem PhosGuard is a very good product to remove brown algae, diatoms, and other types of algae you don't want in your aquarium. Highly recommended.
B**V
Great profuct
Best price in large quantity
S**L
Need Confirmation
I received the packet yesterday, however the container is very old and lot of scratches even the container was not sealed and it was open. I am worried if this is not a used product, stickers are pulled out . I am worried as it may completely mess up my marine setup. Kindly comment please.
A**S
Work well
Bought this as was having trouble with fluffy algae and biofilm was significantly more than normal. So to help get the tank under control I purchased this. It's worked great and helped sort the rank and get back to normal. You don't need much at all
Trustpilot
1 month ago
1 month ago