If you have a hydroponic crop with a data logging and automated control solution, you probably have a lot of sensor and control data recorded that could be useful to take your crop’s results to the next level. In this post, I am going to talk about some things that you could be doing with these stored data. You will see how the usage of this data opens up many possibilities and that even implementing the most basic of these suggestions could lead to important improvements in your understanding of your crop and its results.

The lowest hanging fruit to take advantage of logged data is to be able to download the data and put it into a database structure that you can properly query and search. Most data logging solutions record the data in either very simple structures, like csv files, or non-relational databases – like MongoDB – which are rather limited and do not allow for the degree of versatility that a true relational database engine offers. Having the data in a properly built database will allow you to start using it in a creative way. For example, with the data in a proper database, it becomes possible to create a custom data visualization that can help you understand what’s going on inside your growing environment.

The images in this post show you some examples of this. The first one shows a simple example where a rather noisy humidity sensor is smoothed out using different moving averages, these averages can then be used to implement more effective control algorithms. The second image shows a detailed map of the temperature and humidity values experienced in a room, colored by the hour of the day. We can use this plot to easily locate where problematic times and VPD conditions might be, just by looking at when extreme readings happen. This behavior would be harder to observe and diagnose on a regular VPD Vs Time plot. Regular data logging web interfaces and platforms will not allow you to create plots of this sort, which is why putting your data into a proper DB and manipulating it to create custom visualizations can be very powerful.

The most powerful uses of the data come into play when you actually piece together your control and sensor data. Say you have an AC system coupled with a temperature sensor but you have a lot of other temperature and humidity readings and you also know the age of your plants at each point in time. Using this, you can create an advanced control algorithm where a system will use all of this additional information to know when to trigger AC systems and dehumidifiers to control the environment. Having a lot of logged data from a set point control system is a great starting point to train a reinforcement learning algorithm for climate control, since we know which control actions were taken at each point in time and we know the effect these had. Implementing such control mechanisms can lead to control systems that avoid spikes in humidity and temperature across light on/off cycles, greatly smoothing out the environmental transitions for your crops.

Finally, there is also the potential to improve yields by gathering detailed mappings of yield data in a room and relating these yields with environmental sensors. If you have several different sensors in a room and you know the yield that you obtained on a per-plant basis, then you can create a map of all the yields in a room in order to see if there are important disparities in your yields because of differences in local humidity, temperature, light or air circulation levels. This can lead to important insights that can help better adjust climate conditions for the entire grow room. If multiple rooms are available, the information about environmental sensor data can be related to yields in order to stir all rooms towards more favorable conditions.

For example, after analyzing yield and temperature data from multiple growing cycles of one of my customers, we realized that the greenhouse with the lowest temperature standard deviations between sensors was giving the best yields, we then implemented better control algorithms on the other greenhouses to prevent this from happening, obtaining significantly better results across the board after that.

Data is a treasure. If you have been recording judicious sensor, climate control, and yield data through time, you’re probably sitting on a gold mine that you haven’t exploited yet. If you’re interested in using my help to do so, please consider booking an hour of consultation time with me so that we can discuss your needs and how we could leverage your data to improve your growing results.

On a previous post, I discussed a very interesting open-source sensor/data logging alternative for Hydroponics called MyCodo, which offers a lot of features and flexibility for those growers with the time and skills necessary to implement their own sensor and data logging setup. However, many growers don’t have the time to do this on their own – or the time and willingness to hire someone to do it for them – and all they want is a solution that “just works” out of the box and that fits most of their data logging needs. In this post I am going to talk about three commercial solutions – in no particular order – that I’ve had experience with along with some of the advantages and disadvantages that each one offers you. Note that this post has not been sponsored by any of these brands. The statements below represent my opinions on the matter and the facts, to the best of my knowledge. I recommend you contact each company to ask specific questions pertinent to your needs.

Growtronix. This company offers a complete solution for monitoring and automation of hydroponic crops. Their sensors are hooked through cabled connections and they support a wide array of analogue sensors, both sold by them and by third parties. As long as a sensor can work on a 3.5-5V input and give an analogue reading, it can be installed in a growtronix setup. Their web interface is user-friendly, it allows you to view sensor readings and create control schemes using simple if logic statements. They have also shared the source code of their web interface with some of my customers in the past, so if you would like to customize things beyond their base web application, I’m sure you could figure it out if you have the time and programming skills. Growtronix support – per the experience of the customers I have you have used it – has been stellar.

There are however some downsides to using growtronix. Since everything is cabled you will need to lay cables across your rooms if you want to hook up multiple sensors within them. The system lacks support for third party i2c sensors, meaning that you can only connect analogue sensors and will miss on some interesting third-party sensor offerings. The data is also stored in a non-relational mongoDB implementation, which means that querying data and doing complicated data analysis will not be easy with them. Their control algorithm technology is also rather simple, to the best of my knowledge they do not offer more advanced control mechanisms beyond the if logic statements they allow the users to program.

Agrowtek. Similar to Growtronix, they also offer a complete monitoring and automation solution for hydroponic crops. However, they offer their own touchscreen computers to connect to their sensors, dosing pumps, and relay modules, so they do not have a dedicated web interface for their sensors that is hosted on any computer but you must purchase their own. Their “GrowControl” panels will hook with normal ethernet cables to any of the sensors they offer and you will be able to program all the behavior of the sensors and the relays from these stations. Their main advantage is easy setup, everything easily hooks up and you can then program things within the GrowControl panels to fit whatever simple control needs you might have. You can probably setup 200 sensors/relays in a day to control an entire facility using this setup. Their custom computer also gives you more stability, meaning crashes of the system are rare (according to the customers I have who have used them). From the three companies discussed in this post, this is also the only one to offer nutrient injection systems in their offering.

However, one big limitation of this company is how closed the ecosystem is. You have absolutely no ability to hook up third-party sensors and sadly their offering lacks some important and basic sensors for a medium to large scale hydroponic setup, specifically water content and water potential sensors. You are also becoming reliant on the availability of support from them and – if the company went under – it would be very hard for you to be able to fix or find replacements for their sensors or their control panels. Their control algorithms are also fairly simple and are limited to basic if-logic, similar to the Growtronix system. Data is also not logged into any database but as basic csv files, which means substantial effort will be needed to perform advanced data analysis tasks.

SmartBeeControllers. This company also offers a complete automation and monitoring solution for your hydroponic crop. Their main differentiating factor relative to the last two is that sensor stations connect wirelessly to your computer, allowing you to place sensors throughout your facility without having to set up cables through the entire place. Their sensor stations can hook up to a large number of sensors so, for example, you can use a water content station to hook up six of their capacitive water content sensors. They also require a computer server with the web software to communicate with – alike Growtronix – and their software has a focus on simplicity. In this case, control options are even more limited than in other cases, with basically only simple set-point logic available to control relays (to the best of my knowledge).

The SmartBee ecosystem is also quite limited and offers no pH/EC/ORP sensors or water potential sensors (tensiometers). You have no ability to hook up third-party sensors as well, meaning you’re stuck with this offering if you use them. Because of the wireless nature of communications, sensor readings and their stability can also be compromised due to excessive electromagnetic noise, which can be particularly problematic in a short room that has a lot of HPS ballasts. It is also true that in the past (2-3 years ago) their support seemed to have problems, with several complaints about their response time online. I do not know if their technical support has improved so I would advise you to seek recent opinions about it on social media if you’re considering them for purchase. The people I know who used them didn’t need to contact support, so I cannot comment on this aspect from my customers’ experience.

The above are three commercially available data logging systems for hydroponics. All of them should be easy to hook up and should provide you with basic data logging and control capabilities for your grow. In my opinion, the most complete one is Growtronix, given the ability to add third-party sensors – even if only analogue ones – and the quality of their sensors and web application software. However, if controlling the nutrient injection process electronically is important for your situation, then Agrowtek might be a better solution. None of them however provide advanced control mechanisms – like reinforcement learning-based climate control – and none of them provide access to all sensors that would be desirable, so a custom DIY setup might be best if these features are very important to you.