Before You Start: The 5 Golden Rules of βMacGyverβ
- Use food-grade materials. Look for markings PP, HDPE, LDPE, PET, PVC-U for potable water.
- Say βnoβ to light. Paint transparent plastics (non-toxic paint) or wrap them with foil to prevent algae.
- Electricity under RCD protection (residual-current device) and use a drip loop in cables β so water drips away from the socket.
- Always do a 24h leak test on your balcony or in the bathtub before adding plants.
- Cleanliness. After assembly, rinse everything with warm water + soap, then disinfectant solution according to the label.
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System 1: NFT with Gutters / PVC Pipes (as in the pictures)
For whom? Lettuce, herbs, strawberries β fast growth, clean, and compact.
Idea: A thin layer of nutrient flows along the channel bottom with a slight slope, roots rest βon the filmβ and breathe.
What to Buy (sources)
- PVC gutters 100β125 mm with end capsor PVC-U sewer pipes Γ110 mm + end plugs (DIY store: Castorama/OBI/Leroy).
- Circulation aquarium pump 600β1200 l/h (pet shop/online).
- Hose 12β16 mm for supply + fittings/quick-connects (plumbing/gardening).
- Bulkheads 20β25 mm for drainage (plumbing supply).
- Reservoir container 40β80 l with lid (HDPE) (DIY/online).
- Net pots 50β80 mm + clay pebbles/rockwool (garden center).
- Hole saw bits 51/60/76 mm (hardware store).
- Frame: aluminum profiles/metal rack or shelving (DIY).
Step by Step Assembly
- Plan hole spacing in channels: every 20β25 cm. Last hole at least 10 cm from the end.
- Drill holes with a hole saw (clean cuts, no jagged edges), smooth with sandpaper.
- Set slope 1β2% (1β2 cm per meter). Place channels on rack shelves β each shelf slightly lower.
- Drainage: at the lowest end install bulkhead 25 mm β hose flows back to the reservoir.
- Supply: pump β hose 12β16 mm β βTβ splitter β fittings above channel inlets (drip/stream).
- Seal ends (end caps/plugs) with aquarium silicone after full cure.
- Block light: paint channels/pipes with matte plastic paint, or wrap with black foil + white tape (cool & clean).
- Fill reservoir (nutrient), start pump β adjust flow so it runs as a thin film (not a river).
Diagram (side view)
[SUPPLY] -> _________ _________ _________
| |---->| |---->| |----> [DRAIN -> RESERVOIR]
(pump) |_____/_| |_____/_| |_____/_|
slope 1β2% slope 1β2% slope 1β2%
O O O O Β· holes for net pots (every 20β25 cm)
Starter Parameters (general, for greens)
- Reservoir level: 2β3 cm below drain (room for slope).
- Flow per channel: 1β2 l/min (lettuce); bigger plants β 2β3 l/min.
- Solution pH: 5.8β6.2 (standard hydro).
- Cleaning: once/week wipe channel with sponge-on-stick; between cycles rinse + disinfect per label.
Estimated cost: β¬75β150 for 3β4 channels Γ 1.5 m (with pump, reservoir, and rack).
System 2: DWC with Buckets and Totes (simple and effective)
For whom? Herbs, tomatoes, peppers; roots submerged in nutrient, air provided by diffusers.
What to Buy
- 20 l food-grade bucket with lidor60β90 l HDPE tote.
- Large net pot 140β200 mm (inserted in lid) + clay pebbles.
- Air pump with 1β4 outlets + air stones + silicone tubing (aquarium shop).
- Check valve for each airline (prevents backflow into pump).
- (Optional) Water circulator 200β400 l/h for mixing.
Assembly in 15 Minutes
- Cut hole in lid for net pot (hole saw/knife).
- Set up aeration: stone on bottom, to pump through check valve (arrow pointing into bucket).
- Block light: wrap container walls with foil/tape.
- Fill with nutrient: initially so that 1β2 cm touches net pot bottom; later lower 2β3 cm once roots hang.
Cross-section Diagram
Lid ββ(net pot)ββ
| roots β
|~~~~~~~~ Nutrient (60β90% of bucket)
| (air stone)
|____ tube β check valve β air pump
Estimated cost: β¬25β55 per site (depending on pump and size).
Hacks:
- Instead of one large pot β make a multi-cup lid (4β6 small pots).
- If water warms in summer: wrap in white foil + add cardboard βtentβ over bucket (shade).
System 3: Passive Kratky Box (zero pumps)
For whom? Lettuce, basil, pak choi β fast growers that like calm.
What to Buy
- 30β60 l HDPE container with lid.
- Net pots 50β80 mm + βgridβ lid (or drill holes in lid).
- Starter medium: sponges/fiber/clay pebbles.
Assembly
- Drill holes in lid: spacing 15β20 cm.
- Fill with nutrient to 1β2 cm below pot bottoms β at start it may touch, later plants will drink and create an air gap.
- Block light β no algae.
Diagram
Lid (holes) o o o o
Net pots β β β β
================= Nutrient =================
(air gap grows as plants drink)
Estimated cost: β¬15β30 per container (4β8 plants).
Where to Get Parts (easiest)
- DIY store: gutters/pipes, elbows, end caps, profiles, hole saws, aquarium silicone.
- Plumbing/gardening: hoses, fittings, ball valves, bulkheads.
- Aquarium shop: pumps, stones, check valves, thermometers.
- Garden center: net pots, clay pebbles, starter cubes, simple pH/EC meters.
- Online: splitters, quick-connects, racks, matte plastic paints.
Typical Sizes and Holes (cheat sheet)
- Net pot 50 mm β hole saw 51β52 mm.
- Net pot 76 mm β hole saw 76β78 mm.
- Bulkhead 25 mm β hole 32β34 mm (check model).
- NFT slope 1β2%.
- Vertical spacing (lettuce): 25β30 cm, for bigger herbs: 35β40 cm.
Nutrient, pH, EC β Quick Guide (universal)
- pH: 5.8β6.2 (most hydro plants like it).
- EC: leafy greens ~0.8β1.4 mS/cm; fruiting crops usually higher (depends on species/phase).
- Water: ideally soft/RO + own mixing; at least dechlorinate tap water (carbon filter).
- Changes: NFT/DWC every 7β14 days; Kratky β top up with water, full change between cycles.
Maintenance and Cleanliness (minimum plan)
- Daily: quick look β level, temperature, pump humming.
- Weekly: wipe channels, check hoses for algae.
- Between cycles: drain, wash (detergent), rinse, disinfect per label, rinse, dry.
Common Mistakes and Fixes
- NFT slope too shallow β standing water. Fix: lift channel inlet with spacers.
- See-through reservoir β algae. Fix: foil/paint + lid.
- No check valve on airline β backflow floods pump. Fix: β¬0.50 part saves nerves.
- Drain too narrow β overflows. Fix: drain larger than inlet.
- Drilling without backing β jagged edges. Fix: place board under, drill slowly.
Mini FAQ (for clarity)
Are rain gutters safe for nutrient?
Yes, if itβs PVC-U for water (no plasticizers) and you wash + lightproof them.
What water level in DWC?
Start: touching pot, later leave 2β3 cm air gap.
Can I drill without a hole saw?
Possible, but not worth the hassle. Hole saw β¬5β10 saves edges and fingers.
What about pump noise?
Anti-vibration mat + silicone drop under pump. Drip loop on cable = safer.
Two Ready-Made Projects (with shopping list)
A) β12-Plant Lettuce Rigβ (NFT, 3 channels Γ 1.5 m)
- 3Γ PVC gutter 100 mm + 6Γ end caps
- 1Γ pump 1000 l/h + 13 mm hose + βTβ + 3 fittings
- 3Γ bulkhead 25 mm + 25 mm drain hose
- 1Γ 60 l container + lid
- 12Γ 76 mm net pot + clay pebbles
- Rack/frame + screws, plastic paint
Work time: 3β4 h, budget: ~β¬115β150
B) βSilent Farmerβ (DWC, 60 l tote, 6 plants)
- 1Γ 60 l container + lid
- 6Γ 76 mm net pot + starter sponges/clay pebbles
- Air pump 2β4 outlets + 2Γ disc stones + tubing + 2Γ check valves
- Tape/foil to block walls
Work time: 45β60 min, budget: ~β¬38β55
Pro Tips βMacGyver Styleβ
- Label hoses and channels (MARKER: supply/drain); in a month youβll thank yourself.
- Garden quick-connects (green βclickβ) make NFT like LEGO for adults.
- Velcro straps instead of zip ties β 1000Γ easier for servicing.
- Matte white foil on channels = less heat, less algae, more reflected light.
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