Ebb and Flow:

Ebb and flow systems are very popular with indoor hydroponic gardeners. The ebb and flow method, which is sometimes called “flood and drain” is popular because of its simplicity. Ebb and flow systems are easy to maintain and operate, and are able to produce large yields, which makes them popular with many indoor gardeners. However, ebb and flow systems are best used in smaller operations because large flood tables are needed. Ebb and flow systems are also commonly used for rooting cuttings, and vegetating young plants to maturity.

Similar to other hydroponic systems, ebb and flow systems start with plants placed into net pots filled with a grow medium like grow rocks, perlite, or hydroton. Those net pots are then placed into flood tables that are flooded with nutrient solution at regular intervals. Since the garden and the number of plants are limited to the size of the flood table used, many small plants are grown in ebb and flow systems. However, if the grower wants to grow more or larger plants, bigger flood tables may be used.

One of the most important aspects of ebb and flow systems is to have a proper flood (i.e. feeding) schedule for the plants. At regular intervals, a water pump will fill the flood table with nutrient solution (ebb) which then drains back to the reservoir (flow). If the flood schedule is too quick, plants may not get enough nutrition. If the schedule is too slow, and plants sit in the nutrient solution for more than 30 minutes at a time, their root systems could be damaged by sitting in oxygen-depleted water for that long. This is why having a proper flood schedule is very important in ebb and flow systems. The plants should be drained regularly so roots are exposed to oxygen which will help support plant growth.