The self-sustaining fish tank

The self-sustaining fish tank is probably the best of the lazy person’s dreams. This is where they get to enjoy all the benefits without the labor necessary to keep it healthy and functioning flawlessly.
The self-sustaining fish tank

“A self-sustaining fish-tank? Whoever heard of that?”

Who wouldn’t want a fish tank that needs no constant attention and helps you maintain an aquaponics system without much fuss? The self-sustaining fish tank is probably the best of the lazy person’s dreams. This is where they get to enjoy all the benefits without the labour necessary to keep it healthy and functioning flawlessly.

The problem with this is that a person will always have to keep an eye on things and eventually have to intervene when something goes wrong. In order to have a healthy aquaponics system, regular tests for the water’s PH are required to maintain an ideal balance so that both plants and fish can thrive.  This of course rules out the self-sustaining fish tank notion, making it a bit of a myth.

Even if one were to have fully automated systems monitoring and applying the correct doses of chemicals to keep the water at acceptable levels for the fish, they still have to feed the system with the chemicals and food for the fish. These things do not materialize from anywhere…

Can an aquaponics system actually contain a self-sustaining fish tank if these human interventions are necessary? Perhaps a better way to describe them is a “Minimum Intervention System” for that is what they really are.

In terms of maintaining aquaponics systems, there is no such thing as a self-sustaining fish tank since the relationship with the plants is symbiotic. Anything that affects the fish tank will also affect the grow beds. This particularly true of Deep Water Culture Aquaponics systems. The nutrient-loaded water from the fish tank has to be thoroughly filtered to make sure that particles do not clog the roots of the plants. Failure to do so will hugely impact production.

There is nothing that is self-sustaining in nature. Everything has to be nurtured from some source. This is true of plants and animals and even our planet! Everything is an ecosystem that contributes to another.

People who are unfamiliar with aquaponics often lead themselves to believe that it relies on a self-sustaining fish tank or self-sustaining plants. Put one together, and wait for the magic to happen! Neither could be further from the truth. They exist in a symbiotic relationship and they both rely on people to feed and take care of the system. That is where the “ponos” (Ancient Greek word for labour) in Aquaponics comes from.

Is the self-sustaining fish tank a myth?

The fish tank has fish that one feeds, the fish produce waste in the water, the water is piped to the plants which feed on the fish waste, and the water is then piped back clean to the fish tank in a cycle. The plants are then harvested to be consumed and new plants are planted to start the cycle again.

There is no such thing as a self-sustaining fish tank or plants in a closed system. They coexist relying heavily on each other and humans to tend to them. This is what occurs in a closed system such as an aquaponics system. However, things change quite a bit when it comes to large bodies of freshwater found in nature.

A self-sustaining fish tank works only in nature

Nature is basically an engine of unimaginable proportions and balances, even though it may seem chaotic and even destructive at times. Everything that disturbs that balance is counterbalanced by some reaction of nature.

But on a more manageable scale, take for instance the analogy of the self-sustaining fish tank mentioned earlier. If the fish are not fed, they produce no waste which provides no food for the plants. This results in poor growth. Action, Reaction.

If a sizeable natural lake is left alone, without human intervention, and nothing occurs to change its balance, it will provide food for the fish, and the fish will provide nutrient-rich water for the surrounding plants on its embankment. A well-run ecosystem. However, pollute the water and the plants start to recede. Action, Reaction.

How “autonomous” is a self-sustaining fish tank?

This process and analogy, however, are dissimilar in quite a few respects when it comes to large aquaponics systems. No matter how large the system, it will still need human intervention in order to function properly. It will need the energy to drive its pumps. It will need food to provide nutrition to the fish which in turn provides nutrients to the water. It will need chemicals to balance the water to keep the fish and plants happy. It will need piping to transfer the nutrients rich water to plants that must be provided by humans in the form of planting a.s.o.

Compared to nature which is self-balancing and can function without humans, any man-made system ultimately needs a PERSON to function properly.

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