Practical Action

Piloting floating cage aquageoponics system in polders: an innovation to increase fish and vegetable production in polder based farming system


Practical Action developed a solution for co-production of fish and vegetables in the salinity affected Satkhira district of Bangladesh. Aquageoponics and similar other farming solutions can bring revolution in future sustainable farming as it has the potential to give access to waterbody for the poor and commercial entrepreneurs, control water pollution during intensification. Thirty male and female participants (member of Water User Groups) tested this option in 2017.

Floating cages with fish and vegetables in canals


This innovation contributes to the Blue Gold objective of increased productivity, by developing a viable business model of integrated floating cage aquageoponics system (IFCAS).

Female farmer nursing the vegetable plants

The Innovation

The technical key aspects of this system was already researched with further development scope on its business proof. In business modelling different combination of aquageoponics larger cages (9m3) and non-aqua geoponics smaller cages (1m3) were used to understand combination benefits, economic viability and risk mitigation strategies. In both size cages mono sex Tilapia and Climbing perch (Vietnam strain) was stocked at 150- 200 per cubic meter. Mega grower floating feed was applied. Two cycles were run between July to February 2017 (3 months per cycle). Sponge gourds and bottle gourd saplings were planted in tubs floated with the larger cages.

Aquageoponics in a larger pond


It was found that within three months’ farmers can harvest 114 kg of climbing perch (koi fish) worth 17700 BDT (221 USD) from a nine-cubic meter cage and for tilapia 133 kg of fish worth 9542 BDT (119 USD) which was highest 182 kg of fish per larger cage. Major investments were on cage construction (118 USD), and fish seed and feed cost (114 USD/unit/cycle). The cost benefit ratio was 1:1.75 for both fish. Average vegetable production per cage was 16 kg per cycle. As it was closer to their houses women participants found it as a manageable option which can contribute to household nutrition and additional income. They were found interested to continue such options.

Lessons learnt

  • Our pilot investigation confirmed that the business case was profitable with in two cycles where the 1st cycle was the breakeven point.
  • Canals (deeper part) holding year-round water well negotiated with owners, free from crab need to be selected for such systems.
  • Crabs can damage cage net is a big threat. This can be mitigated if the net is tightly placed in the iron frame. Canals near crab fattening farm and jute retting area can be avoided.

Crab damaged cage nets

Future and sustainability

With entrepreneur’s own investment or accessing finance from Bank for start-up the system can be scaled up in other suitable polders and other suitable canals. There is also great potential to take it to water logged areas and large water basins.

Contact: Faruk Ul Islam, PhD; Email:; Cell: +880 1712532388
Study team: Faruk Ul Islam, PhD.UK (Lead researcher); AJM Shafiqul Islam, Aquaculture Expert; Kamrul Islam Bhuiyan, Horticulture Expert; Syed Mahmud Hasan, Information & Knowledge Expert ; M.M. Haque, PhD. Professor & Aquageoponics Expert, BAU; Hasin Jahan, Country Director, Practical Action, Business Development & Water Mgt. Expert

Download a PDF version: Practical Action – Aquageoponics v3