Aquarium substrate affects everything from plant growth and water flow to the comfort of species that dig or rest along the bottom of the tank. Sand or gravel size, the number of holes and channels through it, and nutrients present can all influence how well the substrate supports your aquarium over time. Some substrates work better for planted freshwater tanks, while others help support easier maintenance and long-term durability in other setups. Below, you'll find today's best-selling and top-rated aquarium substrates that Chewy pet parents, like you, love. We update this list every week, so you can be sure you're getting the timeliest product recommendations available.
We leveraged input from our veterinarians and artificial intelligence to identify key considerations to help you find the best aquarium substrate.
We scanned thousands of customer reviews and ratings and scored each product based on its performance against each of the key considerations. We then considered how popular a product is with Chewy customers and combined that with its key consideration scores to create the list of the best aquarium substrates.
Key aquarium substrate considerations
Durability
This is important because a durable substrate will last longer and not break down easily, providing a stable base for your aquarium and preventing any potential harm to your aquatic animals.
Grain size
The size of the substrate grains can affect the growth of beneficial bacteria and the overall health of your aquarium. Larger grains may allow for better water flow, while smaller grains can trap debris and lead to anaerobic pockets.
Nutrient content
Some substrates may contain essential nutrients for plant growth, which can benefit both the plants and the overall health of the aquarium. However, too much nutrient content can lead to algae growth, so it's important to find a balance.
Porosity
A substrate with good porosity allows for proper water circulation and oxygenation, which is crucial for the health of your aquarium's ecosystem. It also helps with the breakdown of waste and debris.