Pick The Best Phosphate Remover for Your Tank

It’s frustrating when you see those high numbers on the phosphate checker. These levels of phosphate aren’t harmless for your fish. So what do you do? 

High phosphate levels can make you pull your hair out. But you can deal with them quickly. But with so many options, which phosphate remover do you prefer?

We’ve gone through the trouble, so you don’t have to. That’s right; we’ve gathered 5 of the best phosphate removers after going through 20.

This article should help you choose the best phosphate remover for you. You’ll also have an insight into the buying guide towards the end.

We’re going to be sticking to traditional phosphate removers for now. So let’s get into the reviews without any further ado. 

Comparison Table

On top of the list, we have this little guy from Brightwell Aquatics. All the products on the list do the same thing. It’s up to us to decide which one does it better.

And this liquid phosphate remover hit a home run, right? Let’s talk about it. 

The MicroBacter7 works as a water conditioner. So you might expect this to make the water better. Well, that’s the plan. But how well is the plan executed?

Well, Brightwell Aquatics claim that this one is good for both fish tanks and aquariums. We can’t say for sure, as the fish tank we had wasn’t in testing conditions. 

But the product seemed to work well in the aquarium that we had. We previously checked the phosphate levels with a checker. And then, we compared the results after using the remover.

To our surprise, the liquid phosphate remover worked. It claims that it removes nitrites, ammonia, nitrogen, nitrates, and organic carbon in most aquariums. 

But we only had the phosphate checker in our reach at the time. So we’re not too sure about the other elements. But it’s safe to say that the phosphate levels did go down after using this one.

They also claim that this liquid is quite effective against different enzymes and microbes.

This is a good thing, if it’s true, that is. But we didn’t have the proper mechanism to check that in the first place. 

Brightwell says this will dramatically improve the water inside the fish tanks or aquariums. We’re not too sure about the whole water improvement thing. 

But we’re here to examine if it can reduce phosphate levels inside the fish tanks. And it does the job quite well.

So if you’re looking for a cleaner aquarium substrate, this could be a top choice.

Another thing that felt interesting to us is how the liquid improves water clarity. This surely struck us by surprise. We weren’t expecting this to live up to the promise.

Although the brand claims that the liquid increases the growth of photosynthetic organisms, we didn’t have enough time.

So we couldn’t check out the full potential of this remover.


  • Improves water clarity
  • Reduces organic carbons
  • Boosts growth of photosynthetic organisms
  • Increases dissolved oxygen concentration
  • Reduces pre-existing phosphates


  • Slow to act
  • Not too effective against ammonia

Next up on our list, we have this resin phosphate remover from Fluval. They say the chemical filter media works well against phosphate, nitrate, and nitrite. We’ll see about that.

Unlike the first one on the list, this isn’t liquid. It’s more of a dry mixture that promises to reduce and remove phosphate. But we had to put it to the test.

Upon testing this out, we saw that the filter media could reduce phosphate levels.

We used a phosphate checker to compare the results before and after applying this powdered substance.

Let’s talk about what we found good about this product. The first thing is that they include three packs inside the box. 

Although we could check the phosphate levels decreasing, we can’t say the same about nitrate and nitrite. That’s because we were equipped to test the phosphate levels.

So we couldn’t manage the other types of tests to check out whether the company’s other claims were valid.

But this works considerably against phosphates. You might even be intrigued to pick this up instead of the top one. That’s because you probably can’t manage a better deal than this one.

It’s true because this product does a lot for the price. But there’s still a lot that it doesn’t do. So if your only objective is to go for the cheapest option, be my guest and pick this one.

When it comes to water clarity, this one seems to work. We won’t say that you will get crystal clear water as they claim.

But it gets the job done. You will still see substrates in the water; they won’t be as visible as before.

Many of you might be intrigued to know whether this powdered chemical would work in different conditions.

We had a couple of aquariums lying around while testing this remover.

We used a pack of this in a saltwater aquarium and the other in a freshwater one. To our surprise, the phosphate levels changed.

The company tells you to replace it monthly for the best results. We had to get the review out, so we didn’t get a chance to observe the results for a month.  

We would still say that the way this resin scientifically absorbs phosphates is interesting. But we have to say that it works. It may not completely get rid of algae, but it does help.


  • Enhances water clarity
  • Reduces nitrites, nitrates, and phosphates
  • Long-lasting effect
  • Keeps the water clear
  • Works for three water-changes 


  • Regular bag changes needed
  • It takes a long time to work

Now, this is a big one. Coming in third place is this large container full of phosphate remover. And there’s a big problem with this one. No matter how good this is, you can’t get it in a smaller size.

Sorry about starting with a bummer. Those who need smaller quantities would be likely to skip this one. 

Seachem is known to work well with its test kits. But we had to test this phosphate remover to know whether they were good at everything.

They claim that their PhosGuard is good enough to eliminate phosphate from your tank rapidly.

It might remove the phosphate all right, but we’re not too sure about the “rapidly” part. You’ll know why in just a bit.

They also claim that the remover successfully removes silicates from your reef tanks.

But we didn’t test that out. That’s because we were focusing more on the “Phosphate removal” parts of these products. 

In terms of ease of use, we’ll say this is easy enough to handle. But you have to be careful as the mixture might produce heat when it comes in contact with water.

So, where exactly can you use this phosphate remover? Well, the company claims that you can use this in the media chamber and the canister filter.

We haven’t tried to use this in-the-box filter, but they claim you can do that.

What bothered us was that you had to leave the product for four days to get results. You have to leave the PhosGuard in the reef tank till the phosphate levels drop.

But if you see no change in the phosphate levels, the company asks you to leave it in. This sounded pretty unbelievable to us.

I mean, why should I keep on waiting for this if another phosphate remover can do a better job?

So we’re deducting points from Seachem for pulling this trick on us. 

But it’s a good thing that they warn you not to over-treat the water. They also recommend using smaller quantities over time than all at once. 


  • Promotes easy water flow
  • Removes silicate and phosphates
  • Works in both marine and freshwater aquariums
  • Quickly changes phosphate levels
  • Nullifies brown algae growth


  • Generates heat when it comes in contact with water
  • It doesn’t remove algae directly 

Coming in at the second last place is this GFO phosphate remover from Kolar Labs. And our understanding is that they aren’t too flashy with their packaging. But are they good enough to secure a place in your reef tank?

First things first. We like that you can choose different sizes. You can order the 8.81oz pack if you want smaller quantities. And if you want a bit more than usual, you can select the 1lb option instead. 

So we appreciate that they give you options, unlike the top three on the list. 

From a chemical perspective, the granular ferric oxide is effective against phosphates.

The composition is enough to reduce or even eliminate phosphates. But using them in a reef tank is a whole other topic.

Since Kolar Labs said this works like a charm, we had to put it to the test. And they kind of lived up to their words.

When we checked the phosphate composition in the tank before, and after using this phosphate remover, a change was visible.

But it’s the other claims that made us skeptical. I mean, it says that it fights algae. What they should’ve mentioned is that it’s an indirect process.

Let’s keep this short. The product effectively reduces phosphates. This eventually reduces food for brown algae. Since they have no food sources anymore, they die off. 

Although they talked about how this product works like a charm for all aquariums, we had to put it to the test.

After further testing, we saw that the phosphate levels changed in freshwater and saltwater fish tanks.

So if you’re looking for a phosphate remover that can reduce phosphate levels in both tanks, this could be an optimum choice.

They also claim that this works in ponds and reef tanks. But we haven’t tested that out yet.

Here’s an all-important question. Where can you use this product inside the aquarium?

They said it works in reactors, canister filters, and filter socks. You can probably use them in the filter cartridges too.

It’s a good thing that they warn you to rinse the product before use. This is specifically important if there is any dust on the product.

You might ask why we put this one so low on the list if it’s that good. Well, we didn’t think that it was worth the price to put it anywhere near the top, especially because you can get better value-for-money options. 

But truth be told, this product holds its own. So we can still recommend you use this for your koi ponds. 


  • Removes arsenic, heavy metals, and silicates
  • Prevents algae growth
  • Promotes a healthier fish environment
  • Safe for fishes
  • More effective in filter socks and reactors


  • On the expensive side
  • The granules may be too small


Coming in at last place is this phosphate remover from D-D. While it’s the only product on the list that offers five different size options, we’ll talk about why it ended up in the last place.

Let’s talk about something we appreciate about this one. This is the only one on the list that provides a 5kg option.

So if you’re on the hunt for a phosphate remover that will last for a long time, this could be it.

This is also a decent choice if you have multiple fish tanks. The brand claims it’s suitable for reef aquariums and marine fish tanks. Unfortunately, we didn’t have a reef tank to test things out.

But when we tested this with our marine fish tank, we noticed a dip in the phosphate level. So props to the product for not lying to us.

They also claim that the product doesn’t leech the phosphate back into the water after absorption. This is a pretty common concern.

That’s because many cheaper removers leech the absorbed phosphates back into the tank.

After further testing, we found that you shouldn’t worry about this particular issue using this one. 

In terms of negatives, this product has a few notable ones. It takes a lot of time to reduce the phosphate levels in a tank. You might not even see a difference in three whole days.

Another big problem that we faced is that the product is quite messy.

This means you might rinse a lot of the product down the drain without even knowing.


  • Offers multiple size options for versatility
  • Beneficial for multiple fish tanks
  • Works for both saltwater and freshwater
  • Works well upon rinsing
  • Easy to apply


  • Small grain sizes
  • It takes too much time to work


Buying Guide

Now that we’re done with the reviews, it’s time to make the purchase decision. Hold on a second. You still have to learn about the different factors to consider.

Now we’ll discuss what you need to keep in mind before buying. 

Getting the Most Out of Your Money

Price is one of the most important things to consider before making such purchases. You would want the best product for your fish, but you probably wouldn’t appreciate the big hole in your pocket. 

So always pick the phosphate remover that’s sure to get the job done, keeping you within budget.

With that said, there are also quite a few non-branded phosphate removers lying on the corners of different marketplaces.

We recommend that you avoid those and stick to renowned brands for now.

Quantity Matters

Not everyone has multiple reef tanks in their homes. Most of you may only have one of them. But some people have multiple fish tanks. 

For these people, it’s essential to buy in bulk. The problem is not all the products come in bulk sizes. Only two of the products on our list hit the 1-liter mark. 

But one of them even offers a 5kg option. So you have to keep this in mind while buying.

Aquarium Compatibility

You might buy a phosphate remover that works for saltwater tanks, only to find out that you have a freshwater tank.

This situation is all the more common now. Luckily, some brands are switching to solutions that work with saltwater and freshwater aquariums.

Some of them even go as far as working with koi ponds. You get the gist.


Question: What’s causing a higher phosphate level in my tanks?

Answer: Fish excrement, decaying food, and waste breakdown eventually pile up to increase the phosphate levels inside your tank.

While lower levels aren’t too harmful, the higher phosphate levels can cause algae blooms.

Question: What’s the most significant disadvantage of phosphates?

Answers: Too much phosphate will cause higher algae blooms. Brown algae will consume more oxygen from the water. So eventually, your beloved fish will have to compete for oxygen in their homes. 

Question: Is chlorine effective against phosphates? 

Answer: Yes, some might even call chlorine the best algaecide. That’s why some phosphate removers incorporate chlorine in their products. 


That’s it from us. If you’ve gone through this correctly, you should have a clear idea. So you can easily pick the best phosphate remover for you. 

Check the phosphate level in your tank before and after using any of the products. Whether you go with the cheapest or the most expensive option, you will notice a difference for sure.