In this article, we will be comparing the Ebb and Flow (Flood and Drain) system against ALIEN's RAIN™ system.

What is Ebb and Flow?

With the Ebb and Flow technique, plants are cultivated by transplanting seedlings into a plastic or fabric pot filled with an inert medium, such as rock wool, clay balls, or perlite. Typically, the pots sit on a plastic tray with raised grids and are positioned above a nutrient-rich water reservoir. Water floods the trays via a pump, and the plant roots take up the water through the bottom of the pots.

Water then recirculates back to the tank, allowing the roots to dry and oxygenate before flooding with water again.

What is the ALIEN RAIN™ System?

The RAIN™ System consists of pots filled with a medium of the grower’s choice and showers water onto the soil's surface in a rain-like effect. The system can be set up as a recirculating system or a run to waste system.


One significant advantage of the ALIEN RAIN™ hydroponic system is that it gives the grower more control over the plants and helps prevent diseases. The most common issue for growers using a Flood and Drain system is root rot caused by bacteria and fungi. In a recirculating flood and drain system, fusarium (soil fungi) and pythium spores can travel to all the other plants in the system. The spores generated from the infected plant are then transported from the infected plant pot to the reservoir in a recirculating system. They then mass produce in the water reservoir and infect all the plants in the system. This cannot happen when using the RAIN™ system set at "Run to Waste" because any excess water leaving the pot is expelled out of the system and is not recirculated through the system.

The RAIN™ system's plant pots are covered with lids, whereas Flood and Drain systems do not have this feature. In the RAIN™ System, the pot lid covers the soil's surface, blocking out light, eliminating top-surface algae and enabling the plant’s roots to use the growing medium right up to the surface. This, in turn, can lead to increased plant yields. In the Flood and Drain system, the surface of the medium is always dry, so the salt accumulates.


Despite similar features, both the run to waste and pot lid factors give the ALIEN RAIN™ system the leading edge in this comparison. You can view all ALIEN RAIN™ systems via the ALIEN Hydroponics website.