A loop, not a chore.
Fish, bacteria and plants do the work. You feed the fish and harvest the greens — the system handles the rest.
The Living Larder · Aquaponics
Build · Sep 2026
Food that grows itself.
A closed-loop garden where fish feed the plants and the plants clean the water — fresh salad, herbs and greens grown with no soil and no chemical fertiliser, a few steps from the kitchen.
- Closed-loop
- No soil
- ~90% less water
- Year-round greens
What it is
Two tanks, one quiet loop between fish and plants
Aquaponics joins two simple things: a tank of hardy fish and a bed of growing plants. The fish feed the water, friendly bacteria turn that into plant food, the plants drink it clean, and the water flows back to the fish. It runs on a small pump and a little electricity — and it turns a corner of the retreat into a living larder guests can watch, taste and learn from.
Barely sips water.
Water circulates instead of draining away, using a fraction of what a soil garden needs — ideal for dry Norte summers.
Greens all year.
Lettuce, basil, mint, kale and chard keep coming, close to the kitchen, picked the moment they're needed.
A story you can taste.
Guests see exactly where their salad came from — a calm, beautiful teaching tool, not a hidden farm shed.
How it works
The nitrogen cycle, made visible
Fish waste is rich in ammonia. In the grow bed, bacteria convert it first to nitrite, then to nitrate — the natural fertiliser plants love. The roots take it up, the water leaves clean, and the cycle begins again. The honest beginner path is staged: run it as plain hydroponics for the first two weeks to learn the plumbing, then add hardy fish once the loop is stable.
Built in stages
From a safe test loop to a full living system
We start small, prove the plumbing, then grow it. Three honest stages, no shortcuts.
Stage 1 · Hydroponics test
Run the loop with no fish for two weeks — pump, grow bed and bell siphon only. Learn the rhythm with zero risk to any animal.
Stage 2 · Hardy fish
Add goldfish or carp (never tilapia in Norte Portugal). Cycle fishless for 4–6 weeks first, then stock at half density and watch the water.
Stage 3 · The living larder
A settled two-tank system feeding the kitchen — IBC fish tank, gravel grow bed, salad and herbs in steady supply for the retreat.
See it
Seven printable cards
The whole system on a handful of cards — how it works, what to grow, and how to keep the water healthy. Click any card to open the full image.
Listen & build
A short audio primer — and the full build guide
Prefer to listen? Start with the quick audio teaser, then take the illustrated step-by-step guide to the field. Everything is shared openly in our Resources library.
Audio in English
Lusitano Retreat
Come and build the loop
The aquaponics system is one of the first things we raise during the September build sprint. Come and learn it hands-on, or follow the build from afar.