How to Pick the Best Black Soil Aquarium

black soil aquarium

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Your choice of aquarium soil surface layer can greatly influence the health of your aquatic plants and tropical fish. So, if you want to record explosive plant growth alongside healthy betta fish, you should find the perfect black soil aquarium sand substrate!

But just how do you go about finding this type of substrate layer?

What are the most important things to consider when looking for the ideal aquarium plant soil?

What are the best tank substrates in this category?

Keep reading to find the best black earth substrates for freshwater aquatic plants and animal life today!

1. Seachem Flourite Black Sand Quality Substrate

As far as large and medium business brands go in the aquatic community, Seachem is as popular as it gets. Seachem Flourite specifically has been an incredibly popular and reliable substrate over the last decade.

Besides carrying the name of one of the most beloved business brands in aquatics at the moment, this aqua soil substrate had a lot of good things going for it from the get-go.

The highly porous, inert aquarium substrate initially appears very similar to coarse-grade substrate sand. Upon closer inspection, you’ll quickly see that the texture and size of this sandy substrate helps it better adapt towards supporting the optimal growth of both small and robust roots.

Unlike heavier substrates, it won’t weigh your aquatic plants down while doing this. Also, because it doesn’t contain any harmful substances, it won’t influence the water parameters in the aquarium. No need to worry about acidic water, water hardness, or any other worrisome issue.

Something you should keep in mind moving forward is that these types of substrates don’t contain nutrients themselves. As such, you’ll need to complement the aqua soil substrate with water column fertilizers and root tabs.

Aquarists who want a simple and affordable commercial substrate they can rely on for long periods of time will find a lot to love in Seachem Flourite aquarium soil.


  • This soil substrate is inert.
  • Has a suitably large and high surface area.
  • Supports both fragile roots and larger roots efficiently.
  • Is a reliable product from one of the top aquatic business brands at the moment.
  • Doesn’t influence water parameters like water acidity or cause any muddy water issue.
  • Perfect for the average planted fish tank size.


  • Requires root tabs and water column fertilizers to actively contribute to the growth of aquatic plants and beneficial bacteria.
  • The soil can get very dusty if it isn’t rinsed thoroughly.

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2. CaribSea Eco-Complete Black Aqua Soil

There’s a reason that seasoned aquarists call this aquarium substrate plant soil for fish tanks a “complete substrate”.

You’re not going to find many aquarium plant soil types that offer you as much as these bags of substrate would in the price range that they come in.

If you’re out for a nutrient-rich substrate for optimal plant growth in your fish tank, you stand to gain a lot by leveraging the mineralogical and biological balance this product affords you.

This quality substrate ensures explosive plant growth and improved aquarium bacteria health by supplying the habitat with sodium, potassium, zinc, sulfur, and a host of other macro and micronutrients.

This aqua planting substrate also has a decent visual appeal as well because its finer grain size results in the perfect, stylish backdrop for your beautiful plants and fish.

It’s easy to see why this type of substrate layer is hard for many people to pass up. CaribSea Inc. truly outdid themselves with this one.

However, we should mention that this soil substrate may not be the ideal option for a shrimp tank. A tank with shrimp will likely suffer from the introduction of this aqua soil as it has the potential to increase water acidity.


  • This aqua soil substrate isn’t nutrient-depleting.
  • Ensures explosive plant growth, even without the introduction of water column fertilizers and root tabs.
  • Is a completely natural soil substrate with no artificial colors.
  • Finer grain size results in increased aesthetics.
  • Encourages the increased activity of bio-filtering bacteria.


  • Affects water parameters and can cause water acidity.

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3. Ultum Nature Systems Controsoil Planted Aquarium Substrate Soil

No black soil aquarium list would be complete without tipping a hat to Ultum Nature Systems’ Controsoil. This aquarium substrate plant soil for fish tanks is a highly competitive product that enhances the water habitat extensively while putting it at minimal risk.

One of the things we love the most about the nutrient-rich substrate is that it affords your aquatic plants and bio-filtering bacteria all the resources they need to thrive.

Because it keeps the release of nitrogen from ammonia to a minimum, it’s more suitable for a broader range of aquatic species. So, if you’re looking for one of the safest aqua soil types for your ornamental shrimps, this is it!

The level of management involved in keeping this aquarium plant soil in shape is negligible as well. As the soil is designed to actively absorb impurities on its own, it may be the ideal substrate for people who won’t have the time to rinse their aquarium soil as often as they’d like.


  • Promotes the growth of aquarium bacteria.
  • The aquarium soil is rich in nutrients.
  • Requires a minimal level of management.
  • Doesn’t significantly impact aquarium water parameters.


  • Current price tag makes it one of the more expensive substrates at the moment.

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4. UP Aqua Sand Substrate for Aquatic Plants

While inert, clay-based substrates have their advantages as well, an organic aqua planting substrate like UP Aqua will make you forget what those are. This sandy substrate combines the best of actual organic soil and clay to give your aquarium a surface layer that eagerly supports life.

We’ll confess that it was tough choosing UP Aqua over ADA Amazonia Aqua Soils. However, the former excels at two things over the latter.

The first is that these fish tank substrates keep the pH of the water firmly within a range of 6.5 to 7.0. As water pH has a great influence on aquatic life, the fact that this soil helps you achieve a biological balance gives you more options to work with.

No washing is required, nor does this device leak residual ammonium into the water.

For those who want nothing short of the best in their aquarium, this active substrate is the way to go!


  • Makes for a more relaxing surface for your ornamental shrimps and tropical fish.
  • Doesn’t leach residual ammonium into the aquarium and it regulates water pH levels.
  • Doesn’t require rinsing.
  • Doesn’t cause any muddy water issues.
  • Level of management required to maintain it is lower.


  • One of the more expensive substrates on the market.

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5. Fluval Betta Aquarium Gravel

Unlike its sister product, the Fluval Plant and Shrimp Stratum, the Fluval Betta isn’t a volcanic soil substrate. That being said, this layer of gravel is no less amazing.

To start with, this is a completely inert aquarium substrate, so you don’t have to worry about harmful substances (like toxic ammonia) messing with the ecosystem of your aquarium. There’s no risk of your aquarium developing alkaline water or acidic water.

Sadly, this also means that this aquarium gravel won’t contribute appreciably to foliage growth either. But we feel this finer pea gravel sand substrate amply makes up for this with its high level of affordability.

This is arguably one of the best natural gravel bags you can get if you want to increase the aesthetic appeal of your aquarium habitat cost-effectively. These water tank substrates are just perfect for helping your betta fish or shrimp stand out even more.


  • This natural gravel sand substrate is more affordable.
  • It’s aesthetically pleasing.
  • Doesn’t affect water parameters.
  • Fosters the growth of plants with delicate roots.
  • Available in multiple color options.
  • Has an especially soft and smooth texture so it’s less likely to hurt your betta fish.


  • Doesn’t contribute directly to plant growth.

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The Complete Black Soil Aquarium Buying Guide

If you want a substrate that checks all the right boxes, you have to do more than just pick the first product you see. To get the best black soil aquarium, some factors you should consider are the following:

Substrate Material

Predictably, different substrates will influence your aquarium environment in various ways. As each type of substrate introduces different elements into the habitat, you should make sure you go for one that offers the most desired effect.

For example, sand substrates offer no real nutritional value to your aquarium but they’re great aesthetically. On the other hand, aquarium soil will promote the growth and health of all species in your habitat (although it looks less than stellar).

Nutritional Value Potential

The plants in your aquarium require a specific amount, quality, and type of nutrient to survive. In this regard, the types of substrates available to you are divided into two (2) categories. These are:

Inert Substrate

This type of substrate typically doesn’t offer any nutritional value to your planted tank. They’re still preferred because they prevent unbalanced alkalinity and acidity levels and add visual appeal to your aquarium.

Nutrient-Rich Depleting Substrate

A nutrient-rich depleting substrate is the opposite of an inert aquarium substrate, as it contains many of the micro and macro nutrients essential for explosive plant growth.

However, you’ll need to replenish their nutrient supply over time with root tabs and water column fertilizers if they’re to maintain optimum performance levels.

Substrate Weight

Weight is a critical factor because lighter substrates will be more easily unsettled by the movements of your fish. This not only means that your aquatic plants will float around more often, but also increases the risk of damaging your aquarium filter.

Heavier substrates are better in that they allow easier planting and offer a more reliable footing for delicate roots.

Level of Porosity

The higher the porosity of a substrate, the better a home it is for aquarium bacteria. This doesn’t just encourage the active growth of your plants, but also ensures the continued survival of your aquarium.

Baked-clay substrates typically have high porosity.

Level of Management and Maintenance Required

The intensity and level of management needed to keep your aquarium substrate in optimal condition is critical as well. The unique properties of different substrate types mean that the ease of cleaning varies greatly.

But, broadly speaking, sand substrates are the easiest type of surface layer to clean.


Can I Just Use Soil from my Garden or Backyard for my Aquarium?

No, you can’t use soil from your garden or backyard for your aquarium. The most important reason for this is that, except for a few rare cases, soils from your garden and backyard are non-organic.

Placing such soils in your aquarium puts your plants and fish at the mercy of bugs, larvae, and other harmful organisms.

Is Black Soil Too Sharp for Bottom-Dwellers?

No, black soil isn’t too sharp for bottom-dwellers. Even though it might be a little harder than many other substrate types, it’s usually not sharp enough to actually hurt the fish.

Which is Better between Black Soil Aquarium and Bare-Bottom Aquarium?

Black soil aquariums are better than bare-bottom aquariums. This is because the former fosters the growth of bio-filtering bacteria, helps many fish feel safer, and can be more aesthetically pleasing.

Bottom Line

We hope the information we’ve provided will help you make the best decision possible. If you’re still not sure which way to go with your black soil aquarium, fall back to base and prioritize ease of management and visual appeal above all else.

You can also reach our team here for more assistance.

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