Aquarium substrate is the material used in a fish tank base.

The choice of choosing aquarium substrate is up to an aquarist. It also depends on the type of fish you are going to keep.

Gravel is the best pick for freshwater fish

Here are some types of substrates to select.

Aquarium Substrate Bare Bottom:

Bare Bottom Aquarium Substrate


The main advantage of the bare bottom is that fish waste is prominent and, it is easier to clean a fish tank. Having a bare bottom does not involve much maintenance compared to sand or gravel substrates.

 Aquarium Substrate Gravel:

Aquarium Sand and gravel


 Gravels have a variety of colors and sizes. Many people go with gravel when it comes to the substrate. Gravels should not be sharp to save fish from being hurt. Gravels are naturally colored, dyed, or have polymer seals. Sharp gravels are not fit for fish that like to burrow in the substrate. Sharp gravel could hurt their skin. It adds to the aesthetic of a fish tank and pops up fish that you would like to be in your tank.

How deep a gravel substrate should be:

How deep should be the depth of a gravel substrate? It depends on the size of the aquarium. The ideal depth should be 1 to 2 inches for a  fish tank. 

Home for beneficial bacteria:

Gravels serve as homes of beneficial bacteria that break down fish waste and keep water conditions safe for fish. Gravel can be large or small in size. Both have their effects.

 Aquarium Sand:

Sand appears natural in a fish tank. It is easier to see and clean sand. There is no space between sand particles. Fish waste and uneaten food stay on the surface do not get down and trapped in sand. African cichlids eat sand substrate to digest food and thrive. Some fish need sand to hide and sift through sand to find food. The size and color of sand impact the aesthetic look of a fish tank. If water flow is high in a tank will lead to a  tank bare. Choosing the color of the sand is up to the hobbyist's choice. The darker color of the sand makes the fish color more vibrant. White sand substrate gives a light and bright look.

How much sand should be in a fish tank?

  It depends on the size of a fish tank. The ideal depth is one to three inches more than this, which is hard to clean. 

Sand types:

Sand arrives as live sand and dry sand. Live sand is coral sand that helps cycle a fish tank. It has bacteria that dissolve fish waste to make water quality safe. Dry sand comes dry not wet like live sand. Dry sand needs washing before adding to a fish tank. The dry sand will make the aquarium water cloudy when not cleaned.

Substrate cleaning:

The substrate needs cleaning as debris builds upon it. The fish waste and uneaten food collect on it. If not cleared, it will lead to ammonia spikes, which are toxic for fish.

How to clean sand substrate?

Cleaning sand substrate requires a siphon to keep it on the sand. It will pull up the debris out of the water. Don't push the siphon deep if the sand is fine. It can suck up the sand out of the tank. Gently hang the siphon and move it over the sand. If the water flow is good in a fish tank, it can also help waste to removed by the water filter. This process also requires water change up to 10-25%. You will have to clean the substrate once a week to keep the fish safe.

The size of the substrate:

The size of the substrate affects cleaning the fish tank. The pea-size gravels look classic and easy to siphon. Large gravels are challenging as the waste gets trapped in them.

Final words:

As a beginner, it is good to start with the bare bottom tank, for it is easy to go through it than sand or gravel. Go with sand after research and some knowledge. Picking the wrong choice will end up you throwing it out of the tank. Doing research will help you choose the most suitable substrate for your fish tank.

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