How to choose an aquarium substrate?

Before choosing an aquarium substrate, it is favorable to know its primary purpose. Substrates can take on various functions in an aquarium and its biological ecosystem. Before choosing an aquarium substrate, we should ask ourselves: What kind of aquarium do I want to build, exactly?

Gravel substrate

The tropical community aquarium consisting of freshwater plants and fish is often recommended to beginner aquarists. Still, everyone can start with any kind of aquarium. The chances are good that it'll work if one gets well informed before exploring uncharted territory. However, let's begin with an overall favorite, the tropical community aquarium. Small-grained gravel (4-5 cm bottom layer) will probably be the best choice to keep easy and slow-growing plants.

The pictures below show some natural gravels, which are good choices for this purpose. These gravels are pre-washed, so they can be filled immediately into the aquarium without rinsing before. It has no sharp edges because the grains are rounded, which is advisable if you plan to keep bottom dweller fish like a Corydoras Catfish species. Bottom dwellers like these prefer smaller grain sizes; that's why fine substrates would be the top choice on their substrate list. Keeping gravel and sand substrate clean becomes an easy task by using a gravel cleaner.

A gravel cleaner operates simply as effectively as it works like a siphon, sucking organic waste and other dirt particles through the suction valve and the hose out of the aquarium. Therefore, push the suction valve into the ground, the vacuum lifts the substrate, and the waste gets sucked out easily.

Fertilizing Substrate - Nutrition for medium-demanding plants

We can use nutrient-rich plant substrate (1-2 cm thick) and place it underneath the top layer (gravel or sand) as a base layer. This kind of two-layer bottom will offer more nutrients to the plants, which is good for their health and appearance. It can speed up the plant growth rate, too.

How much soil do I need?

An economical solution shouldn't be a problem, as different soil package sizes are available for small, medium, or large aquariums. Don't worry atomic physics study isn't needed to calculate the amount of soil for a certain aquarium size, as the illustrative example will show us:

GIVEN: 64-liter aquarium / 60P (60cmx30cmx36cm) 

GOAL: Get the needed amount of nutrient-rich plant soil and gravel for a two-layer bottom 

CALCULATION: Multiply the base measurements of the aquarium and divide the result by 1000, which will lead to the result.

1 cm thick soil layer: 

60cmx30cmx1cm=1800 cm³ 

1800 cm³/1000=1.8 liters 

5 cm thick fine-grained gravel layer: 

60cmx30cmx5cm=9000 cm³ 

9000 cm³/1000=9 liters

Clay-based substrate - plant soils

In the world of soil, there is a unique type. The clay-based soil is also called aqua-soil or aquarium plant soil. Using these soils in the aquarium is recommended if there's a focus on plant keeping. And in case someone likes to delve into the beautiful world of aquascaping, only these nutrient-rich, clay-based soils should be considered. 

Use aqua-soils alone or with a fertilizing substrate layer underneath it (the right amount of fertilizing substrate can also be calculated with the above method). But soil cleaning with a gravel cleaner sucking the debris out isn't a good idea. Why? Because these baked clay granules can stay in shape very well underwater, even for years, but they can't withstand being crumbled or shaken strongly. And there is no need for it because these soils are also called active soil. Active means bacterial colonies (in/on the soil) can break down organic debris into nutrients that plants can take up; this is a huge treasure for the plants and the aquarist.

Decorative sand

Finally, there is one more type of substrate. Amongst aquarists, it's well-known as decorative sand. 

Aquascapers use decorative sand to create riverbeds, simulate shorelines, or build paths. Some aquarists swear on using only this type of substrate without any other substrate. And, of course, this would be suitable for certain kinds of aquariums, just like a South American River Biotope aquarium, for example.

Decorative sands are beautiful, no doubt, but sooner or later, the light-colored sands tend to get a dirty look. Their light color makes algae more visible, too. Regular maintenance can help a lot to keep the sand clean. Yet sometimes cleaning won't be enough, and you may think about exchanging the sand, partially. Especially bottom-dwelling fish and shrimp would be pleased to have fine sand in their aquarium. But fine substrates will compact more quickly, and organic substances may get trapped in the bottom, which can influence the biological ecosystem in the aquarium negatively.

Do you need help choosing a suitable aquarium substrate?

You're not sure what substrate is a good fit for your aquarium. Our customer service would be delighted by helping to find a suitable substrate for you. Indeed, we will help you with other questions regarding aquariums and the beautiful world of aquascaping, too!