There are many types of aquarium substrate to choose from nowadays; substrate choices range from neon colored gravel to all natural looking sand types. The substrate is an important place for beneficial bacteria to grow but choosing the right type can be a bit of a challenge, as each substrate type has a different effect on your aquarium and fish.
Basics to starting a Planted Tank - The Planted Tank
Those bacterial colonies are necessary to eliminate waste produced by the fish, leftover food, and plant debris in the aquarium. If the bacteria don't have a comfy gravel bed to live in they will find other places, but may not grow in sufficient quantities to keep the aquarium safe for your fish.
Freshwater Aquarium Gravel : What You Should Know | Home Aquaria
The “old” way of thinking is to use a deep layer of gravel to house bacteria and create space for deep plant roots. Recently, however, this practice has been contested by aquarists who point out that deep gravel and sand beds trap debris and may promote anaerobic bacteria growth that can lead to harmful hydrogen sulfide gas pockets, as well as deter root growth (anaerobic bacteria is also an important piece to the cycle of breaking down ammonia). It’s also true that using a gravel vacuum on deep layers of gravel will send old waste and debris into the aquarium, causing harmful spikes in levels of ammonia, nitrites, and nitrates.
What kind of gravel to use in a planted fishtank
Aquarium substrates, the gravels and sands of tankbottoms, perform several functions in planted tanks; as root anchors,ballast for weighing down nutritive soil, possibly acting as buffers,mineral sources, even inorganic catalysts! Heck, they also make thesystem a lot more natural and attractive. Imagine tanks with barebottoms; no thanks.Some plants and animals you may keep in your aquarium have strong preferences for either sand or gravel substrate. For example, many species of cichlids need sand substrate in order to thrive since eating particles of sand help them digest food. Goldfish, on the other hand, risk suffering from an intestinal blockage if they accidentally ingest sand and so should always be housed in gravel substrate. Aquarium plants also have preferences for sand or gravel, so make sure to research the needs of the plants and animals in your tank before committing to sand or gravel.