How To Remove Silicates From Aquariums? 4 Must-Try Methods

Silicates are going to cover your tank and ruin how beautiful it looks. So do not allow them to destroy what you have built.

This article will show you how to remove silicates from aquariums with four effective methods. You can also learn some pro tips to prevent their growth.

Let’s scroll down to discover!

How To Remove Silicates From Aquariums?

Silicate is an anion made up of oxygen and silicon atoms. These substances may be present in your tap water.

Certain substrates, primarily silica sand, have a fast dissolution rate and can release silicates into the tank water.

Silicates in and of themselves do not pose a severe threat to aquarium inhabitants, but they significantly impact how diatoms appear.

Before the algae seize control of your aquarium, please think of how to handle it.

We recommend four methods that work in almost any case. Don’t forget to consider your situation and opt for the most suitable treatment.

Remove the source

How do silicates form in your fish tank? There are multiple reasons for it. Luckily, you can find the best solution for each.

  • Tap water

The silicate content of your tap water may be excessive because of the natural source. For example, some rivers may have too many dissolved silicates.

Moreover, water processors may add silicates to the water to prevent copper and lead from leaking into the water from the pipelines and increase pH levels.

  • Substrate

Your substrate may have quartz, a valuable rock with low solubility content. However, most quartz you can find in the market isn’t pure.

Some manufacturers state that their silica consists of up to 98% quartz. But even if it’s true, how about the remaining 2%?

The silica sand often contains various minerals that are quick to dissolve and leak undesirable substances into the water.

Commercial sand has added elements to it. So, when setting up your aquarium, choose the substrate cautiously.

Otherwise, you will face a mess when trying to clean your established tank. Things get even harder if the substrate has settled.

planted aquarium

Pay attention to the substrate in your tank

  • Salt

The silicates in a marine tank could have originated from the salt mixtures you use. Introducing table salt to the tank will cause water to leak iodine and silicates.

Even salt mixes for tanks that advertise being silicate-free still have some. To avoid the problem, make sure to choose high-quality salt compounds.

Install RODI units

RODI manufacturers believe that their products completely remove silicates from fish tanks.

But according to some hobbyists, these devices can only effectively extract silicates for a minimal time.

Testing the filtered water is the best approach to be sure. You can also buy pre-made RO water and check it for substances.

If they do, frequent water changes using RO water immediately can solve the issue.

Use removing compounds

Try using silicate-removing compounds too. Put them in a spot where there is enough water flow.

It can be in the sump, filter, or any position with the most water contact.

These substances have a short shelf life. Hence, change the removing materials as soon as you see any indications of brown algae.

Install a protein skimmer

This mechanical filter assists in removing organic molecules from water by the filtration system before they can degrade and produce ammonia.

The protein skimmer will remove unconsumed food, toxins, and waste, raising the dissolved oxygen levels. It will also enhance the water quality.

aquarium with mechanical filter

A mechanical filter can help

How To Prevent The Growth Of Silicates In Aquarium Water?

Now you have removed all the unwanted substances in your fish tank, but it’s not the end. They may come back at any time.

Hence, we are offering some tips to prevent silicates from forming again.

Install a robust filtration system

Most of the time, poor filtration systems cause silicates. So, ensure that yours works effectively, removing irritating substances from your fish tank.

Also, try to keep the filter in good condition. Cleaning and checking your system regularly is the best way to maintain it.

Do not overfeed your fish.

Food waste is a part of brown algae. As a result, just feed your fish enough food.

To avoid overfeeding, divide their meals into intervals, and they won’t leave anything behind in their habitat.

Do not use food with silicates.

Food with silicates undoubtedly harms your tank because of its silicate ingredient. So never feed your fish without first checking the food’s contents.

Change the tank water frequently.

A clean environment is beneficial for your fish and minimizes silicate expansion.

If possible, avoid tap water. Alternatively, fill your fish tank with RO water to remove silica from your tank water.

clean water tank

Change the water regularly to keep your tank clean

Frequently Asked Questions

1. What is the best silicate remover?

Many hobbyists try Seachem PhosBond Remover and have a good experience.

It can rapidly remove silicate in your tank and is safe for freshwater and marine use. You can learn more about this product right here:

2. Are silicates harmful to fish?

Silicate is not harmful to fish or invertebrates. Yet, you should keep it below one mg/L to prevent the growth of diatomaceous algae.

3. Will carbon remove silicates?

No, even the activated carbon at the highest quality can’t remove silicate.

4. How to identify silicates in your aquarium?

There are two ways to tell if your tank has silicate accumulation:

  • The water will turn brown or rusty.
  • When rubbing your fingers on the tank walls, you feel gritty, or your fingers turn brown.

5. Does RowaPhos remove silicates?

RowaPhos is a special ferric hydroxide molecule invented to remove silicates from fresh and saltwater effectively.


You can remove silicates from your aquarium with some steps. No matter which method you choose, try to do it carefully to avoid harming your fish.

Are our guides easy to follow? If you have any problems, please feel free to ask. Thank you for reading!