What Is Aquaponics?

Aquaponics is a step towards a sustainable and productive future. Combining aquaculture and hydroponics, aquaponics takes the best features of both farming methods and saves you time and money.

Aquaponics Aqua Gardening

How does Aquaponics work?

Fish waste created in aquaculture doesn't go to waste in aquaponics, instead this nutrient is recycled into the plant grow bed for absorption by the plants. Clean water is drained from the grow bed back into the fish tank keeping the system clean and healthy. The necessity to flush aquaculture and hydroponic systems on a daily, weekly or monthly basis is gone. The system doesn't need water changes as the plants absorb the water and nutrient they need to grow. Plants grow at a much higher rate than soil as regular flood and drain cycles in the grow bed let nutrient and then oxygenated air in around the plant roots.

Aquaponics explained in a simple diagram

The Chemistry

To allow the plants to extract the nutrients from the fish waste, there are bacteria that live in the grow bed media. These bacteria convert the fish waste (ammonia) into nitrites and then nitrates that can be absorbed by the plants. The conversion of ammonia into nitrates is often called 'the nitrogen cycle'.

Trays filled with a grow media such as expanded clay pebbles are commonly used for growing plants in an aquaponic system, but there are other hydroponics methods that may be used such as:\n

  • NFT Channels (Nutrient Film Technique) used for commercial hydroponics, mounted horizontally or vertically
  • Wall gardens using rockwool media (see Brisbane City's example in Roma Street Park)
  • Run to waste style growing, by watering vegetables using nutrient rich aquaponic water media such as coconut fibres, peat, vermiculite, perlite etc.

The Fish

Many different species of fishcan be grown in an aquaponic system, and in South East Queensland Jade Perch and Silver Perch are the most suitable and require the least monitoring. Other species commonly grown around Brisbane are sleepy cod and barramundi. At Aqua Gardening we don't recommend stocking fish above a rate of 1kg for 30 litres of water, and ensure you provide an air pump to increase the oxygen intake of the fish and plants too!

Get Inspired!

Imagine, you're just 8 weeks away from baby eggplants and 10 weeks until tomatoes! Minimal attention of the grow bed is required - no weeding or fertilisation. Get inspired with our working aquaponics systems in our Aqua Gardening Brisbane store.