In short, carbon dosing can be an effective way to reducing nitrates in aquariums. Here's a more detailed explanation of how it works.
Carbon dosing is the process of adding small amounts of carbon to an aquarium in order to encourage the growth of bacteria that consume nitrates. These bacteria are often referred to as denitrifying bacteria, and they play an important role in the nitrogen cycle.
Denitrifying bacteria are present in all aquariums, but they typically exist in very low numbers. This is because they require conditions that are not often found in aquariums, such as low oxygen levels and high organic matter levels. By adding small amounts of carbon to the aquarium, we can create these conditions and encourage the growth of these beneficial bacteria.
Once these bacteria have established themselves, they will begin to consume nitrates and convert them into nitrogen gas, which escapes from the water and leaves the aquarium. This process is known as denitrification, and it is a key part of keeping nitrate levels under control.
Carbon dosing is not a magic bullet for solving all nitrate problems, but it can be a helpful tool in many situations. It is especially useful for new tanks that are still cycling or for established tanks that have experienced a spike in nitrate levels. If you're struggling with high nitrates, give carbon dosing a try!