Hyduino - Automated Hydroponics With an Arduino




About: "Things don’t have to change the world to be important." Twitter: @PancakePatrol, Google+: Austin Simonson

So, you may be wondering...WHAT IS HYDROPONICS?

Basically, hydroponics is growing plants without the use of a traditional dirt medium by using a nutrient rich water solution. Those mediums used to "plant" in range from fiberglass to sand and from fired clay balls to nothing at all. Several branches of hydroponics include aeroponics, aquaponics, etc. But WHY would I want to take all this extra time and effort to grow my plants in this "special water"? Well, hydroponically grown foods not only taste better and are more nutritional, you can change the properties of your food, monitor what goes into your food and pollute less. You can also grow more in less space. This is especially great for those people that that have limited areas in their backyard to grow in. With the right plant selection, you can also keep pests away; a citronella plant has oils that keep away mosquitoes and other pests. Now if this wasn't enough for you to jump right in to hydroponics, listen to this: hydroponics uses 70 to 90 percent LESS water than conventional growing does.

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Step 1: Gather Your Supplies

To build the Hydruino, you're going to need to first gather some supplies.

These aren't necessarily the cheapest places to get these items, so if you're not in a rush, consider searching on a place like dx.com or on other eBay listings (may or may not be shippnig from China) to find the best possible deal.

Step 2: Building

What I ended up doing was constructing basically a "table" for the system to sit on. The weight of the water in the drain pipe makes it heavy enough for it to easily stay on without a problem. The nice thing about this is that it can be easily scaled to almost any size and all the instructions stay the same (except for the actual construction of the system of course) - there would be no need to change the code...maybe just things like adding more lights, fans, etc.

I don't have a digital copy of all the dimensions of the pipe if you're looking to make a replica of what I've done, but I'll try to get everything entered in within the next couple of days.

For the reservoir, you'll need to drill two holes for the float sensors - one at the very lowest your water can be and one at the top - and also a hole for the solenoid to fit in (which you will glue in). To connect a garden hose to the solenoid, I used 3/4" hose to pipe adapter made by Orbit (found at Home Depot) and a 3/4" to 1/2" reducer to get it down to the right size.

Once you've constructed the frame, you'll want to wrap the entire thing in a transparent plastic, of which you'll have to cut out a couple holes for your fans. With the drain pipe, you'll want to drill out about 3 1/2" or so holes with a hole saw so your pots will fit in. Cut a hole in each end of the drain pipe - one is where water is pumped in from the reservoir, the other is where water drains out back in to the reservoir to be recirculated.

I never got finished with the container for everything to fit into, however, I'm sure that shouldn't be a problem for most of you to figure out. I took the cardboard that my relay shield came in and am working on getting everything to fit in there, since that's a really easy way to put it all together, but you can use whatever you'd like.

Step 3: Wiring

Here is a list of the pins:

  • A1 - Photoresistor
  • A2 - pH Sensor
  • 7 - Lower Float Sensor
  • 8 - Upper Float Sensor
  • 20/21 - RTC
  • 43 - pH Min Peristaltic Pump (Relay)
  • 45 - pH Plus Peristaltic Pump (Relay)
  • 47 - Solenoid Valve (Relay)
  • 48 - Grow Lights (Relay)
  • 49 - Fans (Relay)
  • 50 - Temperature/Humidity Sensor
  • 53 - SD Card

For the float sensors, you're going to have to add in a resistor on each, as shown here, for it to work effectively with your Arduino.

Step 4: Code

Attached is the most current Arduino code for the project. It will be updated based on feedback given by others; I don't expect my way to always be the best way! I haven't had weeks to test it "out in the real world" so there may still be a few kinks in it. Be sure to adjust the lux value for measuring the time for the supplemental lights...the optimal value may vary depending upon your sensor. Also, if you're using a different pH sensor, the calculations may need to be changed to fit that particular one. Big thanks to BillieBricks for working out a lot of the code.

Most Recent Update: v1.0 - November 10, 2014

Step 5: Congratulations!

Congratulations! You've successfully (hopefully!) built your first (or second, or third...) hydroponics system! You're now able to grow your plants in a smaller area while also using less water. Remember that you'll have to keep track of how often to add nutrient mixture. This system could be easily modified or scaled to fit your needs/desires. Please feel free to leave feedback, especially on the code, as there is always room for improvement and it will only help everyone!

Also, please vote for me in the Microcontroller Contest! It would be amazing to have any of those prizes that they're giving out! Thank you!

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    67 Discussions


    Good.... project...

    I feel that there are many one who buy it with some plants with ethernet shield to control via internet.


    4 years ago on Introduction

    For your next project, and the last word in hydroponics automation, combine this with one of the spectrometer projects on Instructables to give a readout of the nutrient concentrations and a mechanism for adding them based on the measurements. :-)

    no problem! thanks for the compliment! It wasn't *too* time consuming after I had planned everything out. If you had all the parts or were able to go to a local store to get them, you should probably be able to finish it in a weekend.


    Reply 4 years ago

    It's funny finally seeing a project such as this on here. I have been toying with the idea for a little while and using the Mega ADK. However...have you looked into the use of a different light spectrum? The F3 light spectrum works fine to mimic summer early fall...but Nasa has released the X5. 6500 Kelvin white with blue mixture. Also...a varient of the octostroller would work but would require a beagle bone to drive it and a 60amp power supply for the 5v. Still yet...great design!! I've honestly debated on using MISO/MOSI and controlling other microcontrollers to do pH.

    Once again...THANKS FOR SHARING!!!


    4 years ago on Introduction

    Great project, I am working on my own, but if I didn't, I would probably have used your design.

    One question though. In the pin numbers you mention pin 53 for SD chip select, but you use pin 51 and 52, which are used for communicating with the SD card. Is this a typo or is this really true, cause if it is, you won't be able to use the SD card.

    1 reply

    You're totally right in pointing that out! Yes, apparently I mistyped the pin numbers in the list...thanks! Good luck on your project!


    7 days ago on Step 4

    Thanks for posting bud. Got my controller all made and gonna take a look how you did the coding . See if i can steal some inspiration


    Question 7 months ago

    hi, austin!
    I'm a middle school student who would like represent your code in an international competition. i will give you and all of your associates full credit in my project. Please let me know if this would be acceptable. thank you.


    Question 12 months ago on Step 5

    Austin good works congratulations. I do not know anything about arduino. Can you sell your complete hydruino to me? I want to make experiments on hydroponics and your tool would fit.


    1 year ago

    How much did all the parts cost roughly?


    1 year ago

    Great idea! Thank you for sharing!


    1 year ago

    Thank you for this project.

    Brother, you can create tutorials on TFT Screen Programming.

    So that we have the flexibility to make another Progaram.


    2 years ago

    Do you have any pictures where you pump in the water to circulate it? Thanks


    2 years ago

    hello. i have this problem .... help please !!!!!

    C:\Users\peeva\Downloads\FSR83MHI2G1F678\FSR83MHI2G1F678.ino: In function 'void setup()':

    FSR83MHI2G1F678:123: error: 'class DateTime' has no member named 'get'

    start_time = now.get ();


    C:\Users\peeva\Downloads\FSR83MHI2G1F678\FSR83MHI2G1F678.ino: In function 'void LightControl()':

    FSR83MHI2G1F678:1548: error: 'class DateTime' has no member named 'get'

    seconds_for_this_cycle = now.get() - seconds_elapsed_total;


    FSR83MHI2G1F678:1549: error: 'class DateTime' has no member named 'get'

    seconds_elapsed_total = now.get() - start_time;


    exit status 1

    'class DateTime' has no member named 'get'