Build a Simple Ebb and Flow System

Hey all.

Last year I was going to do an ebb and flow system but decided to go another route (DWC just looked way cooler!). This year, I’m going to give it a try.

I rummaged through the stuff I had bought last year and put it all together tonight. I’ll be sure to get a video of this system in action once my plants are big enough for it.

How it Works

Ebb and flow diagram


After creating the image above, I initially thought that there would be no need to explain ebb and flow any further, as the image so clearly illustrated the mechanics of this system. I gave it a little more thought though, and decided that maybe it’d be best to provide some supplemental information for the stragglers.

In an ebb and flow (or ebb and flood) system, you have a reservoir, a flooding table, a timer, a submersible pump, and an oh shit this thing is going to overflow emergency drain, or OSTTIGTOED. Here’s how it works:

  • You fill the reservoir with water or a nutrient solution, and place the pump in the reservoir (it’s best if the reservoir is sealed off so no light is hitting its contents and causing algae problems, etc.).
  • The pump connects via a length of tubing to a fill valve that’s cut into the flooding table, and whenever your timer turns the pump on, the pump fills the flooding table with solution from the reservoir. I’m using a 160 gallon per hour pump and it seems to be a good match for a system of this size.
  • The flooding table is what you put all your plant containers in – when it floods, they’re surrounded by water from the bottom up, which encourages better root growth and gives them a good soaking (you can control how high the water flows by adjusting how long the timer remains on for). After the timer kicks off and the pump stops, all the solution then drains out through the same fill valve it came in, and back into the reservoir.
  • If you set your timer too long or the fill valve plugs when it’s draining and the water level ends up coming up too high, this is where your trusty OSTTIGTOED saves the day. The diameter of this drain is significantly larger than the fill valve, and if the water level makes it up to the top of the drain, it is quickly and safely spilled back into the reservoir below.


Ebb and flow components

  • I’m using 2 large tote containers. The little beige one with handles (bonus!) fits into the big blue one. The beige fella is a 10 gallon tote and the blue is 18 gallons. I would have liked to find a shallower version of the beige one, in order to make more room for water in the blue one.
  • I got the submersible pump and the fill and drain kit from Amazon. The kit includes tubing for both the fill and drain valve and looks like this:

Ebb and flow fittings kit


Putting this together is a piece of cake.

  1. Drill out 2 holes in your flooding table for your fill and drain valve. Use a hole saw to do this and make sure it’s the right size for whatever fittings you get.

The flood table of the ebb and flow system

2. Insert the fittings and thread on the plastic nut on the bottom side of the flooding table.

Ebb and flow fittings installed

Ebb and flow drain fitting close-up

3. Place your pump in the bottom of your reservoir and measure how long of a piece of tubing you’ll need in order for the pump to reach the fill valve in the flooding table above. Cut the tubing and connect the pump.

The pump connected to the system

4. Fill your reservoir with water or nutrient solution, and plug the pump in. Time how long it takes (roughly) for the pump to fill the flooding table to the height you want. If it takes 3 minutes, then set your timer outlet to turn on for 3 minutes at a time, at each time in the day you want it to flood. Make sure you overfill it to verify that your drain valve is working properly. You can’t see it, but I just ran the power cord for the pump out the back side, sandwiched between the 2 totes.

Completed ebb and flow system

5. Put your plants in the flooding table, double-check your programmed times, and then get into the Halloween candy stash that your wife bought for you to hand out in a few days but you’ve stolen so much from it already, at this point, it would be better to just eat it all and then replace the box with a new one if you can manage to find time to buy one. It’s not like you were going to hand it ALL out anyways. There’s leftovers every year so why would you wait until AFTER those little shits have picked through all the good chocolate bars and you’re left with Tootsie Rolls and Crispy Crunch?

A bowl of Halloween candy


  1. Crispy Crunch are delicious, you hack.

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