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Using Pool Filter Sand In An Aquarium!

A well-maintained aquarium can be a beautiful centrepiece for your home decor, an interesting biology experiment, or a way to give the kid a pet that won’t tear up the furniture.

No matter what your reason for adding an aquarium to your home, a little bit of helpful advice can give your aquarium a better chance to thrive.

As you get into the hobby of starting and maintaining an aquarium, you might be surprised by how much the needed budget can grow. As you look for alternative options to bring down the cost without bringing down the quality of your aquarium, you may consider using pool filter sand in aquarium construction.

Before you make any major changes to the place your fish call home, read through these common questions to make sure you do it the right way.

Is Pool Filter Sand Okay for Aquariums?

While its name might make you think it’s only for one specific purpose, pool filter sand in aquariums is a viable substitute for other substrates.

The role of the substrate in an aquarium is to support the growth of helpful bacteria and plants by giving them a place to live, and many types of fish – especially bottom dwellers – like to poke around in a sandy layer at the bottom of their environment.

Pool filter sand fulfils both of these needs, so you can use it in place of other substrates without negative side effects for the creatures living inside the aquarium.

Compared to other aquarium substrates, pool filter sand is cheaper while fulfilling most of the same needs.

Specialty brands of aquarium substrates may have features that pool filter sand does not normally have, such as live bacteria cultures intentionally included. It’s a better alternative substrate than play sand, which has a tendency to clump and is difficult to clean.

As with any addition to an aquarium, always check the specifics of your tank, equipment, and fish before deciding to add a material to your tank. Some equipment may be sensitive to smaller particulates and only intended for large substrates like gravel.

Certain types of fish may have similar issues with clogged pores and gills when they live in a sandy environment. Any specific advice should override the general advice given by these answers.

What Kind of Pool Filter Sand Is Safe for Aquariums?

When picking a brand of pool filter sand to fill your aquarium, be mindful of any additives included with the sand. Occasionally, companies will include extra chemicals like chlorine that are a plus for someone maintaining a pool.

If used in an aquarium, these chemicals will leech into the water and poison your fish, impacting their health and potentially killing them.

Generic pool filter sand should be suitable for most aquarium applications. It is typically a grade 20 silica sand, meaning it has a relatively large grain size for sand. You may see ‘D.E pool filter aids’, which are diatomaceous earth supplements for pool filter sand and not the same thing.

While it is safe for most animals and plants, you still don’t want to accidentally add it to your aquarium. It also costs more than pool filter sand!

Does Pool Filter Sand Raise the pH of Your Fish Tank?

An aquarium’s pH level impacts the livelihood of the plants and animals inside of it. Before you add anything to your tank, evaluating what impact it has on the pH level will help keep your creatures alive.

Pool filter sand is made from silica, and it has a neutral pH level. In most cases, this is exactly what an aquarium wants, since the owner can adjust the pH through other methods as necessary.

If your aquarium design intends to rely on a type of sand with a pH impact, you will have to make up for the lost pH changes elsewhere.

Some pool filter sand brands have additives that are intended to ease the problems of pool operators, and these are never an acceptable option for an aquarium. Chlorine in particular has a very high pH level, so any extra in the pool filter sand can have a dramatic impact on the pH level.

Most pool filter sand will be the basic variety, but it is important to remember to keep an eye out for the special versions. Otherwise, the pool filter sand should have little to no impact on the pH level.

How Do I Clean Pool Sand for Aquariums?

Before adding pool filter sand to an aquarium, the sand should be rinsed and cleaned to remove particulates. If the sand is not washed before use, then the dust and other particulates will float through the water, making it murky and potentially damaging the fish or filter.

Cleaning the sand takes a few minutes per bag, but the time spent is worth it if you want to see your fish thrive. You should also clean the sand whenever you do a general cleaning of the aquarium to remove settled particulates.

To clean the sand, start by grabbing a large container like a 5-gallon bucket from a hardware store. Open the bag of sand, and pour it into the bucket. Fill the bucket up to above the sand level with water, helping the water mix with the sand while doing so.

Then, give it a thorough stirring with your hands or another implement. Gently pour out the old water while keeping as much of the sand in the bucket as possible, then repeat the process until the cleaning water appears relatively clear.

You can use an old shirt or other large cloth stretched over the lid to serve as a filter.

Do not use any additives or soaps when cleaning the sand. They are not necessary and more likely to cause health problems for your fish than make their environment healthier.

Can You Use Pool Filter Sand for Planted Aquariums?

When you use pool filter sand in an aquarium with a plant, the primary issue is providing the nutrients that the plant needs to grow.

Natural sand is home to a variety of bacteria and nutrients that create a microscopic ecosystem, and aquarium sands frequently come with nutrient-rich components and live cultures of the bacteria. Pool filter sand is inert and lacks these features.

To circumvent this issue, all you need to do is add fertilizer to the pool filter sand. The sand already serves as a viable anchor point for the underwater flora, so giving them the nutrients they need turns it into a livable environment.

You can purchase root tabs that you insert into the substrate every month or so to slowly add the nutrients right to the base of your plants.

Another way that aquarium owners accomplish this is by putting a thin layer of planting soil underneath the sand layer. Finer sands can trap the gasses released by living components in the soil, but pool filter sand’s larger grains give it more room to burp.

You can still add fertilizer tabs, but the soil will provide a solid foundation underneath the sand with plenty of spare nutrients for the aquatic plants.

Should You Use Pool Filter Sand in Aquarium Setups?

For most aquariums, pool filter sand is a reasonable substrate option for the bottom layer of the tank. It provides an attractive appearance while serving the core functions of the substrate.

The larger grains are easier to clean than fine sand, and some fish may prefer it to gravel as a substrate. It’s also very cheap when compared to most specialty sands and other aquarium substrates.

The major concerns when using pool filter sand in an aquarium are avoiding additives that can harm your aquarium and supplying healthy additives if used in a plant aquarium.

As long as you continue to perform other aspects of aquarium maintenance like monitoring your pH levels and regular cleaning, it should have no major impact on the health of fish or plants inside the tank.