RSS 10 innovations of the MindStream Aquarium Monitor

MASA Admin

8 May 2007
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Being the reef aquarium technophiles that we are, we couldn’t spend a whole day at the offices of MindStream R&D without becoming smitten with what this device is, how it works, and what makes it work. If you thought the MindStream is cool, you’re going to be blown away by the laundry list of innovations that it’s taken to make the MindStream concept to work.

Touching the ammonia sensor with bare fingers is enough to a color reaction to the ammonia in our sweat

#1 Photochemical paper – The crux of the MindStream Aquarium Monitor relies on a particular type of photochemical paper. This material is specially designed to react to certain molecules in the water. The chemo-sensitive paper changes color to a very subtle degree, and nearly all of the MindStream’s parameters are read by fluorescent sensors, only ammonia uses a chromatic sensor.

A close look at the microlens clusters and sensors of the MindStream monitor

#2 LED microlens & sensor – The MindStream uses a very specialized method to measure the color of the photosensitive paper. This is a two part system of both shining light onto the material, and reading the incoming light. There are three of these LED & Sensor arrays, two for fluorescence and one for chromatic readings.

The peculiar beam angle of the MindStream’s microlenses

The light from tiny onboard LEDs is channeled around the sensor to fall onto the chemical paper on multiple discrete points. Each of these points then reflect back into the sensors through multiple filters to get the sharpest data peak possible. The multiple values for each chemical paper is averaged and single data points which are irregular are thrown out of the calculation as outliers which could be the result of a speck of dust. We could go on about how this part works but let’s just say that there are a lot of safeguards and smart features that make this crucial part of the MindStream work.

A side view of the 6-layer printed circuit board of the MindStream

#3 6-layer Printed Circuit Board – In pack to cram as much electronics into the smallest possible space, the entirety of the MindStream’s working parts are crammed into a 6-layer printed circuit board. This use of the 6-layer board allows the MindStream to be smaller and thinner but it also shield the internal electronic signals from any kind of interference.

The magnetic induction assembly that powers the MindStream through the aquarium glass

#4 Inductive power – The whole assembly of the MindStream Aquarium Monitor is powered through inductive charging. There is no onboard battery save for a clock battery, but otherwise all power to the electronics of the MindStream are sent through the aquarium glass itself. There are magnets in both the wet and dry side of the MindStream to keep well fastened to the aquarium glass.

#5 Built in level sensor – One thing that isn’t in the fine print is that the MindStream has a built-in level sensor in the neck of the electronics assembly. We can’t recall how the MindStream senses water level that it’s in, but there’s definitely a mechanism built-in to let the MindStream know when it’s submerged or not.

One of the rhodium plated electrodes used to obtain precise temperature and salinity measurements

#6 Rhodium plated elecrodes – The MindStream depends on precise measurements of temperature and salinity to make its calculations of other elements. With this in mind one of the first subsystems that engineers designed for the MindStream is an ultra accurate method of measuring temperature.

The typical method of measuring temperature using a thermocouple, but in aquarium applications these are usually embedded in plastic leading to less than precise temperature readings, and they are not very sensitive either. To combat this the MindStream uses copper electrodes that are coated with Rhodium, a rare and hard metal which has properties similar to platinum.

While it just looks like black plastic, the Zeonex used to build the MindStream is a particular kind of space age plastic that will greatly reduce biofouling

#7  Zeonex – One of the big questions we had for MindStream was how it was going to mitigate the effects of biofouling on their machine and sensors. We were excited to learn that the MindStream uses a new type of plastic developed by NASA for space applications which is extremely impermeable to water. 

Water seeps through plastic at a slow rate but Zeonex is specially designed to be much less permeable. The reduced movement of moisture in Zeonex decreases the possibility of “protein adhesion”, simply put, it is incredibly hard for stuff to grow on the MindSream’s Zeonex parts. Depending on the cost of Zeonex, perhaps we could see this space age material used in all sorts of wet aquarium parts to reduce biofouling and staining.

The Wifi chip of the MindStream is located in the ‘head’ of the machine, itself bein made of biofouling-resistant Zeonex.

# 8 Wireless & cloud based calculations -It is clearly stated that the MindStream has built-in wifi, but there’s also another wireless chip embedded within its 6-layer board. This additional wireless communication chip has been included to pave the way for future accessories and communicating with existing aquarium devices in the future.

Interestingly, the heavy lifting of determining your precise aquarium water chemistry doesn’t happen on the physical MindStream that is in your tank. Instead the photo-measurements of the chemically sensitive paper is sent wirelessly to MindStream’s cloud servers. This aspect of how the MindStream is particularly crafty as it allows the latest algorithms to be used in determining your water chemistry without users ever having to update their device’s firmware.

The RFID tag of the MindStream replacement discs can be seen here in the shape of the little pill-shaped inclusion below the axis.

#9 RFID read replacement disc – The MindStream discs are also packed with lots of features to make them hyper reliable and accurate. Each batch of disc is like a crop of produce in that the chemical papers used inside them are not exactly the same, but they have slight variations with each batch. Furthermore the manufacturer of this photo-chemical paper is always improving the formula.

One of MindStream’s biggest challenges is in calibrating the discs in large numbers, but users will never have to worry about this aspect of calibration. The calibration for each disc is embedded right into a small Radio Frequency Identification chip which is then read by the MindStream so it knows which “crop” of discs it is sensing. The disc’s calibration information is uploaded to the cloud along with the measurements of the chemical papers making the MindStream user experience as seamless as possible.

Measuring oxygen will be one of the killer features of the MindStream monitor

#10 Oxygen & CO2 – Finally, if you think that logging calcium, alkalinity and magnesium is a big boon to reef keepers, you can’t even imagine how much more crucial it will be for us to measure oxygen and carbon dioxide. After temperature and salinity, oxygen and carbon dioxide are the two next most important aspects of water chemistry that helps us keep corals and fish alive. 

The measurement of oxygen and carbon dioxide could lead to some breakthroughs in learning about our aquarium corals because oxygen consumption and production is directly related to their metabolism. Meanwhile carbon dioxide lowers pH, reducing calcification and being able to watch CO2 levels change in real time will help us in learning all the ways to minimize CO2 in the aquarium.

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