It is very effective at removing dissolved organics from pond water, such as stains and discoloration caused by leaves and organic debris. Activated Carbon filter media is also great at removing harmful chlorine and chloramines caused by tap water.
Activated carbon is useful for removing organic pollutants, tannin, smells, and chlorine in pond water.
Activated carbon, also called activated charcoal, is a material used for the chemical filtration of pond water. The term “chemical filtration” refers to the effective neutralization of harmful dissolved chemicals that cannot be removed with regular mechanical or biological filter media. Activated carbon can be considered another layer of filtration media, turning the normal 2-stage (biological & mechnaical) process into an expanded 3-stage filtration process.
Chemical filtration with activated carbon has seen an increase in popularity in recent years, especially with pond owners with fish stocked ponds. It can effectively remove a large range of organic pollutants and chemicals, making it a great choice for improved water clarity and purity.
Activated Carbon removes many common things:
Tannins (Organic color pollutants)
Pesticides & insecticides
Excess fish pheromones
Smells and odors
These are all organic pollutants that normal filter media will struggle to remove on its own. One of the most common is tannins, which is organic color from debris, such as leaves, grass, or bark. This can often leave your pond with a brown color which activated carbon can help reduce. It is also highly effective at neutralizing chlorine from tap water, so would be suitable for water changes or newer pond builds.
Activated carbon is also extremely useful for fish stocked ponds, especially koi ponds, as excess pheromones produced by fish can reduce the growth of surrounding fish. The carbon will neutralize these excess chemicals and bring the water back into a more balanced state for fish.