AquaLoop: A Surface Water Data Buoy System


Facts and figures are regularly on the news alerting us of the accelerating rate of ocean degradation brought about by climate change and unsustainable human practices. In July 2018, a report claimed that 87% of the world’s oceans are dying, and will continue to rise over the years unless there are solutions to the problems of ocean acidification, mercury pollution, ocean warming, coral bleaching, and more…

Local researchers suggested that, the main problem was the lack of data stations near shores and this is proving to be a hindrance especially on long-run and monitoring research activities; needless to say such monitoring is costly and labor intensive.

Such is probably the reason why information on the condition of the oceans, are unavailable or absent. With the Philippines as an archipelagic country, it is hard to monitor our waters since there are only two devices in the surrounding Philippine seas that are actively collecting data because data buoys are very expensive, and to a third world country, one may say that the accessibility to the right tools to protect marine life may be an issue. With that in mind, we have developed the AquaLoop.

The AquaLoop is a surface water data buoy that can offer live readings of pH, temperature, turbidity, and salinity from the waters as the data is sent wirelessly and is stored in an online database. We believe that this system could aid researchers in the conservation of marine life by giving them access to data they need anytime.

Question / Proposal

In just the last 40 years, almost 50% of our marine life population have been lost. If one were to check the reasons behind them, there could be a plethora of global issues that needs to be addressed. These include, but are not limited to ocean acidification, coral bleaching, mercury pollution. In the Philippines alone, the home to some of the world's most biodiverse coral reefs, only 5% of said reefs still exhibit the excellent quality from the last time it was surveyed. Seeing these problems, we interviewed several ocean researchers and got to know some of the more problematic areas. That said, an underlying problem within the act of research itself becomes more apparent.

This problem is evident in the lack of tools an expert needs to solve these problems. This is true for the Philippines, arguably more than most countries, because longitudinal studies are not cost effective, that is why research funding will support it rarely. Another problem in ocean research is tenure and time – this is because in order to conduct research, one would have to go back to the ocean repeatedly, collect water sample, head back to the lab, and analyze it.

Ideally, real time feedback on the status of these areas should be established. This can be done with our proposal of having a system that provides this feedback which is light, easy to maintain, and affordable that can allow researchers to have live surface water data anytime and anywhere.


Over the last ten years, marine monitoring has become a field of major scientific interest as coastal marine systems are particularly vulnerable to the effects of human activity due to industrial, tourist, and urban development. As a result, analysis of these ecosystems has become a primary concern for researchers interested in learning more about the behavior of the marine environment. This is why it is essential to gather information on large spatials in given time scales to assure effective monitoring and to be able to produce solutions can help reduce the negative impacts on these ecosystems and aid in understanding the changes in water.

With the Philippines being part of the coral triangle, it is known to have more species of fish and corals than any other marine environment on earth where the tropical reefs boast a diversity of life that covers an area up to 26,000 square kilometers. Having these resources, it is the responsibility of this third world country to study the changes happening over the reefs as researchers state that we lost roughly a third of all corals in just 20 years.

The reason why studying changes in water are extended is because of the spatial area that has to be covered under a specific time frame to complete the research. Doing this individually and personally, it would take researchers lots of time and energy to complete their research.

Such problems of spatial-temporal coverage and collection of recorded data are addressed by data buoys through integrated sensors. The present market sells these data buoys for prices up to $6000, but to cover a large area, such of that in the Philippines, several of these data buoys will have to be utilized that makes the budget very expensive.

When we interviewed one of the top marine researchers of the country, we were brought to knowledge that the basic surface water data that is required for research to study the changes in the reefs are: pH, Turbidity, Salinity, and Temperature. With these information, one can cover up the basic information needed for long-run researches in an efficient manner through using a data buoy. 

And with our basic knowledge in Arduino, we believed that it was possible to make a data buoy system that comprises different sensors and sends the obtained data wirelessly to the shore to help increase the efficiency of researches. To do it, we had to study the design of buoys (its design and functionality), how they work, the required electronics and programs that can make up the system, and the different scenarios present in the ocean to make an efficient data buoy. 

Method / Testing and Redesign


The most important aspect of a data buoy is its sensors, and to ensure that the sensors we will be using are reliable, we calculated the accuracy of the calibration of our sensors and our algorithms in the code to actual scientific instruments with digital readings. This was done by comparing our programmed sensor's data with data from laboratory instruments.



One of the main cost efficient feature of the device is the use of LoRa modules, a radio frequency transmitter module designed specifically for long-range, low-power communications, that sends obtained sensor data wirelessly. The obtained sensor data will then be sent to the shore where the data will be received by a receiver station that can store them in an online database which can be accessed by anyone, anytime.

Online Database

Since the purpose of our data buoy is to not only send real-time data, but to also allow access to previous data for researchers and marine data analysts, we have integrated PHP in the creation of our database which is integrated on a HTML/Javascript made webpage.

Program Flow

As a result, the proposal would follow this system:



As we want our buoy to aid researchers in long-run researches, we had to consider the different cases in the waters that could affect the buoy's lifespan. Noting all the factors that plays a huge role in the environment of a buoy – such as salt water, waves, sun's heat – we came up with a design concept that utilizes 2 bodies: the hub and the shell.

The Hub

The hub is where all the electronics and sensors will be placed. There is a built-in GPS module within it that allows researchers to track the coordinates of the data's source and is also made up of stainless steel that compromises 3 layers of circuits to maintain balance in the build.

L1: Battery

L2: Controllers

L3: Sensors

In addition to them, all the electronics are powered by a solar panel that charges a battery for usage in the evening, while it is powered by it in the morning; therefore, having the buoy work 24/7. 

The Shell

The shell is a housing for the hub which will make maintenance and repairs on the buoy easier. Considering the waves and salt water that is always in contact with the buoy at the ocean, we wanted the shell to be buoyant and durable under different situations. To do this, we came up with an octagonal build that is made up of stainless steel to avoid rusts and maintain buoyancy. Moreover, it also has handles on its sides for the attachaments of anchors that will allow it to not drift away with the waves. 



To test our product and to validate our work with local researchers, we went to Lian, Batangas – the home of Br. Alfred Shields Ocean Research Center that oversees the protection of local reefs and marine life and reviewed the final product's functionality on open waters and reefs.


Sensor Configurations

pH Sensor

The pH sensor was tested in a buffer solution with the exact pH level of 4.00. However, the pH sensor read the buffer solution with the pH level of 4.096. We computed for its accuracy with the formula: 

After using the formula, we found out that the readings of the pH sensor have a margin of error of ± 2.4%. Thus, the pH sensor has an accuracy of 97.6% when reading the pH levels of a sample.


Temperature Sensor

The water temperature sensor was tested in a saltwater solution with the exact water temperature of 25. However, the water temperature sensor read the saltwater solution with a temperature of 24.90. We computed for its accuracy with the formula:

After using the formula, we found out that the readings of the pH sensor have a margin of error of ± 0.04%. Thus, the pH sensor has an accuracy of 99.6% when reading the pH levels of a sample.


Turbidity Sensor

In order to get the specific turbidity units of a certain solution, we searched for the relationship between the turbidity and voltage readings of the sensor.

The graph of the relationship between the turbidity and voltage was the following:

We used the formula with the following substitution of y = NTU and x = voltage reading.

This formula showed the specific turbidity of a liquid in NTU (Nephelometric Turbidity Units).


Conductivity Sensor

In order to get the value for the conductivity of a saltwater solution, we got the electric current flowing (ohms) through the conductivity sensor. After the electric current was measured, value was reciprocated to have the measure in ‘mohs.’ Mohs can be also referred as ‘Siemens’ which is the conductivity unit for liquids and aqueous solutions.

The conductivity sensor readings was also sensitive to temperature changes, thus we used the formula:

In order to get the Approximate number of Total Dissolved Solids, the conductivity was multiplied by a constant of 0.67.


Global Positioning System (GPS) Test

The module showed the exact coordinates of the shore (13.979805, 120.629561) where we conducted the testing of the device, and when checked in Google Maps, it was accurate.


Software Test 

The obtained sensor data were sent successfully from the data buoy to a laptop in shore using just radio frequencies. The data were later on uploaded to the database where it can be accessed online through a webpage that has not been hosted yet as it will be ready to generate analytic dashboards once the hosting becomes active which is relevant to time series studies.

Attached below are some of the screenshots of our webpage:


Hardware Review

With a waterproof and rigid build, our data buoy has the following specifications that makes it well-balanced along with the distribution of mass in the hub.

Weight: 4 kg

Volume: 11 cm3

Additionally, to have an undisturbed area where the buoy will be, the yellow color represents the sign of "Stay Away" from the international buoy standards.




Documentation while in Batangas:


The final evaluation of the AquaLoop upon testing in Lian, Batangas was a success with the system proven to be working. The obtained sensor data were accurate and when compared to laboratory instruments, they showed a high correlation in results. The GPS module, successfully plotted the location of the buoy with near pinpoint accuracy and the resultant sensor values were then appropriately logged into the database. 

Clearly, the AquaLoop promises a new approach to marine and coastal research relieving reserachers of tedious, and sometimes even dangerous workloads involved in monitoring and data gathering processes through a much more cheaper and efficient data buoy as it is able to collect data through radio frequencies and is able to upload it wirelessly in a matter of minutes with any WiFi connectivity unlike the traditional models where, researchers have to be onsite, to get their data tediously one by one, write it, and then upload it to the database. Moreover, the data generated by the AquaLoop is more is a lot more relevant in monitoring since it can be generated in real time.

The testing in the shore also gave our data buoy an 85% satisfactory result when surveyed among the local reseachers after presenting the AquaLoop and its functions. These results were mostly upon first impression, and the first use of the AquaLoop. In order to truly see the reliability and efficacy of the buoy, long term testing for the modules is required. This is a weakness in our study, along with the small sample size of researchers that have been surveyed.

That said, the suggestions and criticisms from the researchers chosen to evaluate have been taken to heart and we therefore conclude that the AquaLoop data buoy system not only validated our hypothesis, but also opened a new area of interest for other people to encourage ocean research and protect our natural resources.


These are some of the reviews of professionals in the field of our research:

“[On our data buoy] They could also help, for example, provide early warning. Like Seaweed farmers who want to know if the temperature is increasing. It’s a factor that leads to coral bleaching in our neighboring countries… Most of these [developing countries] do not have a lot of scientists specializing on coral reefs. So if we have instruments like buoys deployed over our reefs, monitoring things, that could generate a lot of data that we need for conservation and management of said reefs.”

Wilfredo Licuanan, Director of Brother Alfred Shields FSC Ocean Research Center, De La Salle University


“From the sensors in the ocean, you can collect information about the current chemical, physical, biological content of the ocean. With it, you can understand how things are changing over time in the ocean.”

Jennifer Widom, Dean of the Stanford University School of Engineering


"This work is really good! I am looking forward to it."

- Joanne R. Constantino, Sr. Research Assistant, The Marine Science Institute, University of the Philippines Diliman.

About me

"Nobody is perfect, but a team can be." - Meredith Belbin

We are all students who share the same vision by having different passions and interests that, when brought all together, made a project like this possible. Carlo's long stint for design, hardware, and robotics inspired his other projects as an innovator. Miguel's interest in the environment allowed him to join the Sea Scout organization while he also has several artistic and athletic pursuits such as swimming, mountain biking, and music. Chio's burning passion for software and web development has placed him under the wings of different organizations, such as Women Who Code Manila.

Although we three are at different poles, we still seem to be sharing the same enthusiasm and motivation towards solving a problem that we have only dreamt of doing. This is what started us and kept us going through every phase of the research

We have recently won the National Robotics Competition and have presented this project in our local Department of Science and Technology which pushed us forward to believe that winning this competition, we will dedicate all our works and accomplishments to our late Dr. Maricar Samson, an ocean resarcher and our mentor who wished a lot for us. We started this project just as a simple idea, but after knowing its true potential after everything we've done, we hope it will reach the people who need it the most as we believe that using this competition as a platform will surely move us forward.

Health & Safety

Every stage of research with the AquaLoop was conducted with safety in mind and with vital supervision of mentors. With it, the equipments and tools that are used in this experiment were not only the ones that were handled with caution, but also the procedures itself.

We followed the following safety precautions:

  • Soldering the circuits in the hub required precision and protection. To do it, we made sure to use lead-free solder and had to wear gloves and masks that can protect us from the solder fumes.
  • All electronics were handled with care and caution to avoid any short circuits or static discharges. They were kept in specific containers that are placed at a dry, cool area.
  • During the test in open waters at Lian, Batangas, we had adult supervision to guide us with the process and had proper instrments that can allow us to conduct the test safely.
  • The process of fabricating the body and boards for the build was done under complete adult supervision by using facilities such as CNC (Computer Numerical Control), ..., at MTE Technology Inc.

Bibliography, references, and acknowledgements

This project has been made possible by the efforts of several people from different fields who have dedicated their time and resources for us, and we would like to thank the following:

MTE Technology Inc.

Charles Sunderraj, Nicanor Jr. Labay, Marc Jose Caudilla

Makerspace Manila

Gino Carino, Miguel Cervantes

First Eduspec, Inc.

Morris Bana

De La Salle University

Maricar Samson, Wilfredo Licuanan, Myrla Torres, Mark Villanueva

Mary Vanessa Nartia, Trish Castro

Michael Moneda, Faima Candelaria