A 18 gal opaque tote with 6 net pot sites in the lid, and no pump or power: the plants drink down the water as they grow.
Draft plan, generated from the model. Not yet build-tested.
6Plant sites
18 galTote
24 x 16 inFootprint
about 14 galSolution
2.75 inHole saw
1 to 2 hrBuild time
~$121.60Materials, part estimate
Drawings All dimensions in inches
3D viewnet pots not shownLid, from abovehole centersFront elevationRight elevation
Shopping list $99.60 checked / $22.00 estimated
Item
Store
Qty
Each
Line
Note
18 gal storage tote with lid (Rubbermaid Roughneck, from a 6-pack at $105.19)
Home Depot
1
$17.53
$17.53
opaque, with lid
3 in net pots, 25 pack
AC Infinity or Garden Supply Guys
1
$16.99
$16.99
6 used
2-3/4 in hole saw
Home Depot
1
$22.00
$22.00
hole saw, reusable
Hydroponic nutrient: General Hydroponics Flora trio, 1 quart each
Premier Hydro Shop
1
$44.84
$44.84
Clay pebbles, 4 L bag
Walmart
1
$13.26
$13.26
clay pebbles around each pot
Black spray paint 12 oz (Rust-Oleum)
Home Depot
1
$6.98
$6.98
only if the tote is not opaque
Total before tax
~$121.60
Filled dot: price read from a store listing on Oct 20, 2026. Hollow dot: estimate. Prices come from the master price list, so they change when it changes.
Build steps
Wash the tote and check it is opaque: hold it to a bright light. If any light comes through, paint the outside with two coats of black spray paint and let it dry.
Mark the lid for 6 holes, measured from the front-left corner of the lid in inches as (across, back): (2 1/2, 2 1/2), (12, 2 1/2), (21 1/2, 2 1/2), (2 1/2, 13 1/2), (12, 13 1/2), (21 1/2, 13 1/2).
Drill the holes with the 2.75 in hole saw, backed with a scrap board so the plastic does not crack, and sand the edges smooth.
Fill the tote to about 14 gal with water and add the nutrient to the label's seedling strength. Check pH and keep it between 5.5 and 6.5.
Set a seedling started in rockwool into each net pot, surround it with clay pebbles and place the pots in the lid so the bottom of each cup just touches the water. The roots grow down; the air gap forms as the plants drink.
Before you start
Sized for 6 lettuce or herb plants at 10 in or more apart. Fruiting crops such as tomatoes need 1 site per tote.
Use an opaque tote. Light in the water grows algae that competes with the roots for food. The Kratky method has no pump, so the water level drops as the plants drink: top it up only until the roots reach the water.
Use food-safe totes and tubing. Wash them before use; never reuse a tote that held chemicals.
The shopping list prices come from prices-extra.json and are estimates, not store prices. Verify them before you publish.
Draft drawings generated from the model. Build one before selling this plan.