Generally considered to be a self-sufficient system with regards to fertilization and the addition
of supplemental nutrients. This is because the nutrients received from the aquaculture part of the
system is sufficient in most cases. However sometimes your fish do not provide the right amount
of nutrients for your plants.
In an aquaponics system the fish effluent provides food for the plants. This by-product from the
fish contains ammonia. Bacteria which grow in the water, provided the water temperature is
correct, turn this ammonia into nitrates. This process is called nitrification. It is these nitrates that
the plants use as food. The plants get these nitrates from the nitrate rich water in the grow media.
It is important to create an environment in the water so that these ammonia converting bacteria
can thrive thus provide the necessary amount of food for your plants. Having the right amount of
bacteria in the water is important, otherwise some sort nitrate supplement will have to be added
to keep your plants healthy.
Sometimes potassium and iron can be lacking in the nitrate mixture in the water received from
the aquaculture system. Anything from rusty nails (iron) to seaweed extract (potassium) have
been used to add these minerals to the water.
Having the correct understanding of how to create a sustainable environment for both your
aquatic animals and plants is key to getting most out of your aquaponics garden. Having a
reliable aquaponics resource to provide you with this understanding would also be very helpful.