I' ve used polyurethane foam cubes as growing media for tomatoes in a passive system. The cubes were soaked in nutrient solution before transplanting.

Size of the container:

2 liter, inside in 1 gallon container

Nutrient concentracion (Third cluster)

N: 140

P: 48

K: 232

Ca: 160

Watering:

Manual, 3 times / day.

Growing media

Growing media, close up:

Roots

Tomato plant

Fruit

Same fruits, two weeks later

Upper clusters