For discus aquariums, sand is the preferred substrate as it closely replicates the natural environment of the discus fish, facilitating their typical feeding behaviours. This is also beneficial for many suitable companion species, like corydoras catfish, which thrive in similar conditions.

Texture and Size

The sand should be smooth and non-abrasive to prevent harm to the fish. For areas with plants, the substrate depth should not be less than 5 cm, ideally around 8 cm. If gravel is used, it should also be smooth and not too coarse to prevent food from getting trapped and causing decay. This is particularly important since discus are fed multiple times a day with a variety of foods.

Advantages of Sand

Quartz sand with a grain size of 0.3-0.7mm is recommended, available at hardware stores or via wholesalers. One major benefit of sand is the ease of cleaning, as food and waste do not sink deep into the substrate but remain on top, making it easy to vacuum.

Indicator Species

Small round snails, often introduced inadvertently with plants, are not necessarily harmful; they serve as good indicators of overfeeding and water quality. A sudden increase in their population suggests excessive feeding. If they climb up the aquarium glass, it may indicate that water conditions need to be checked, particularly since toxin concentrations are highest near the substrate.

Beneficial Snails

Malaysian trumpet snails are particularly useful as they not only indicate overfeeding but also aerate and stir the substrate, helping to remove any remaining food residues. If the population of these beneficial snails becomes too large, they can easily be removed during routine substrate vacuuming.

Additional Tips for Maintaining Your Substrate

To ensure a healthy environment for your discus fish, consider the following tips:

• Regular Vacuuming: Regularly vacuum the substrate to remove any uneaten food and waste, preventing the buildup of harmful toxins.
• Monitor Water Quality: Keep an eye on the water quality by testing it regularly, especially if you notice changes in snail behaviour or population.
• Plant Care: If you have live plants, ensure they are well-maintained, as they help maintain a balanced ecosystem in your aquarium.

Creating the perfect substrate for your discus fish not only enhances their natural behaviour but also contributes to a healthier and more aesthetically pleasing aquarium. With the right substrate and regular maintenance, your discus fish will thrive in their environment, displaying their vibrant colours and lively behaviours.