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Potting Soil Aquariums – What You Need To Know

Potting Soil Aquariums

A lot of the time, fish keepers put so much thought into what goes on the bottom of the tank―sand, substrate, stratum―that it can be hard to figure out what the ideal soil is for your aquarium. Many people wonder whether they can just use potting soil in their aquarium.

Potting soil is safe to use in an aquarium and provides a range of benefits for both plants and fish. Organic potting soil is inexpensive and free from harmful chemical fertilizers, making it perfect for use in an aquarium.

There are many ways you can use potting soil in your tank, and not all potting soil is created equal. The rest of this article will discuss the differences among different types of potting soil and how to use it in your aquarium.

Is Potting Soil Safe for Aquariums?

Organic potting soil is safe for aquariums, but you should never introduce regular old dirt from your backyard into your tank, especially if you’ve used fertilizers or other gardening chemicals. These chemicals aren’t suited for an aquarium setting.

Doing so poses a serious health risk for your fish because you never know what kind of junk you’re introducing to the tank from the outside world. Insects and other contaminants in the soil can wreak havoc on your established tank and introduce a host of pests.

Some regular types of soil you can buy at the store contain dangerous chemicals and fertilizers as well, so it’s best if you avoid anything that doesn’t have an organic label on it.

Organic potting soil or topsoil, on the other hand, is a much better option for the safety of your tank and poses no risk to your fish. Whatever kind of soil you choose to use, it’s important to keep in mind that you can’t just use soil in your tank― it’s way too messy.

Instead, you have to cap off your dirt layer with either sand or gravel to avoid clouding up your water every time you want to do a water change.

Make sure that you dedicate time and effort into capping off your soil properly to avoid dirt escaping into the water column and muddying up your tank.

In addition, not properly capping off your dirtied tank can allow the soil to leech ammonia into your tank, which, while beneficial in an uncycled tank, can seriously harm your fish if unbalanced.

What Kind of Soil Can You Use in an Aquarium?

When deciding what the best way to soil your aquarium, the list of options can feel daunting; however, the best kind of soil to use in an aquarium is organic enriched potting soil, which contains many more nutrients that will be beneficial for plant growth than regular soil.

You can also use topsoil, the best of which is clay topsoil. Clay topsoil is ideal for planted tanks because it provides the best range of nutrients and helps keep the plants rooted. It can, however, get pretty messy to work with.

If you’re insistent on saving every penny and using soil from your garden, then you can sterilize it with a little bit of work. Collect a suitable sample of soil, making sure that there are no large obstructions―leaves, twigs, seeds― by straining it several times.

Spread the soil onto a baking sheet and bake it in the oven for about 20 minutes on 200 ⁰F. Doing so ensures that you kill off any harmful microorganisms that could do damage to your plants or fish.

Be sure to let the dirt cool to room temperature and run it through your strainer several more times to ensure that the dirt is completely filtered.

Once done, you’re free and clear to put the dirt in your tank.

It’s worth noting, however, that while this aquarium soil can be safe, it’s not as nutrient rich as store-bought organic enriched topsoil and won’t have the same beneficial effect on your plants.

Can Potting Soil Be Used for Aquatic Plants?

You can use organic potting soil for aquatic plants. There are, however, a variety of better options on the market if you’re looking to put together a dirtied tank for plants.

A mixture including peat moss, for example, is great because it can store a greater concentration of nutrients that can then be utilized by your aquatic plants. In fact, peat moss is an ingredient in the Fluval Stratum brand of aquasoil.

Dirt mixtures including manure contain nitrogen, phosphorus, and potassium, three beneficial macronutrients that provide ideal conditions for tanks.

Can You Use Miracle Grow Potting Soil in an Aquarium?

Miracle Grow is not designed for aquarium use and poses a health concern for fish. A lot of common soils are designed to promote plant growth with a variety of chemicals and fertilizers. These chemicals, however, aren’t good for fish or the water parameters of your tank.

At best, Miracle Grow is inefficient, with many other fertilizers offering more benefit for near enough the same price. At worst, Miracle Grow potting soil can be deadly for your fish.

Final Thoughts

Potting soil can be used in aquariums, so long as it is organic. There are actually a lot of beneficial types or mixes of potting soil that can be good for aquariums. It’s a lot cheaper than aquasoil and provides a lot of similar benefits.

It’s worth noting, however, that aquasoil is specifically designed for aquariums and is usually the better option if you’re willing to spend a little more to get the best results.

Some excellent compounds in aquasoil, like peat moss, can be found in potting soil mixtures, though, and as long as your soil is organic, it’s perfectly safe to use.

When setting up a dirtied tank, make sure to properly cap off the dirt with a 1-2 inch thick layer of gravel to avoid dirt getting into the water column or the leeching of ammonia.

Overall, potting soil can be a great option for aquariums as long as you source your soil properly

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