Official archive and educational resource of the iAVs research lineage, maintained in collaboration with Dr. Mark McMurtry.
Grow Fish and Vegetables Together — With Sand, Water, and Sunlight
The Integrated Aqua-Vegeculture System (iAVs) uses coarse sand as a combined biofilter, mechanical filter, and growing medium. Fish waste feeds the plants; the plants clean the water for the fish. No synthetic fertilizers. No chemical pH adjustments. No separate filtration equipment. Just biology, working as designed.
Developed at North Carolina State University in the 1980s and validated through peer-reviewed research, iAVs has demonstrated water reuse exceeding 100 cycles, yields comparable to commercial hydroponics, and operation in arid climates from the American South to Jordan to sub-Saharan Africa.
Whether you are building a backyard system or planning a commercial-scale operation, iAVs scales through simple modular replication — the same ratios, the same sand, the same principles at any size.
Proven science. Open source. No gatekeepers.
One input, two harvests: A single bag of fish feed produces both protein (fish) and produce (vegetables) — no additional fertilizer purchases.
Radical water conservation: Peer-reviewed research documents iAVs reusing each unit of water over 100 times, producing 6 g of fish and 17 g of dry-weight vegetables per litre consumed.
Built from what is already there: Sand is globally abundant and effectively free. The system requires no proprietary components, specialised media, or ongoing chemical inputs.
Why iAVs is Different
pH is stable
In a properly configured iAVs, the sand bed and plant root systems naturally buffer pH between 6.3 and 6.5 — no lime, no acid, no daily testing required. This was demonstrated across multiple NCSU trials.
No mechanical filter
The sand bed simultaneously filters solids, hosts nitrifying bacteria, mineralises organic waste, and grows crops. It replaces the clarifier, filter, and mineralisation tank that other systems require as separate, costly components.
No supplements
Fish feed is the sole fertility input. Research confirmed that plants grown in iAVs showed no nutritional deficiencies — every essential macro- and micronutrient was supplied through fish metabolic waste alone.
Empowering Sustainable Food Production with iAVs
Read the iAVs Handbook for the complete system guide, explore the peer-reviewed research, or join the community forum.
Forever alive in our memory.
Gary Donaldson, much loved and respected friend, husband to Jan and passionate teacher and advocate of the iAVs system and master of this website, passed away on Saturday morning 1st July, 2023 at 3:40am.
You will be missed Gary. Your contribution to the iAVs system and helping achieve the goal for food security for everyone will always be inspiring and your lamp will be carried on with those lives that you touched and forever changed for the very best.
Rest In Peace