Passive or active hydro

Dear Ed,
I am planning my first home garden and am confused by contradictory information contained in several books I’ve purchased.

The garden will be constructed in a 2 x 2 x 5 foot cabinet, using a “sea of green” approach. I can’t decide whether I should use a reservoir system or an active flow system. Some sources say an aerated reservoir is good for a simple system, while other sources say the plant roots should not sit in the water. Also, for a flow system, some kits come with submersible pumps, while other authors say never use a submersible pump because the pump will heat the nutrient solution and burn the roots.

Columbia MD

Both passive and active systems will work in the garden. Roots should never sit in water that is not oxygenated. The roots require oxygen and will die if they are sitting in water without it. An inexpensive air pump will supply the reservoir with oxygen by circulating the water. As the water comes in contact with air, it releases carbon dioxide and picks up oxygen.

Small submersible pumps use little power and create little heat. They can be used in reservoirs without fear of boiling roots.

The best advice for small gardens is based on the word KISS- Keep It Simple, Stupid. (Not referring to you personally, of course.)

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