Hi Ian,
Firstly thanks for your email it's great to have someone from the forums actually talk to us.
We are a new and small company working hard to try and increase welfare of fish in captivity, the seneye products have now been in the market for about 9 months.
More information about the products can be found on our website www.seneye.com and a brochure outlining the differences between products can be found here http
/www.seneye.com/marketing.
I'm not entirely sure what is meant by evidence based?
There are a number of technologies (chemistry, physics, electronics, software)employed in the device, is there one in specific you are interested in?
I have included below a walkthrough of the product and how it works.
Obviously we can't give you all of our trade secrets but hopefully the information will provide understanding.
One point to bear in mind is that the product is really invented to be left in aquarium un molested and to send data to our site, it's not intended to be dunked from tank to tank or left to dry out and reused.
Like all ph probes there is a wetting phase and once wet the product should be kept wet.
We invented the product to help people who have absolutely no idea what is going on or are not checking regularly.
It is incredibly good at looking for change and as we all now it is change that more often kills aquarium life than absolute values.
Temperature
This is provided by a pre calibrated digital output sensor that we buy in.
These provide much more consistent results than traditional methods.
NH3 (on seneye+ slide)
We measure toxic NH3 gas in water - we do not reverse calculate.
We measure NH3 optically by firing a known light source at a doped pad. The pad is colorimetric, reversible and highly sensitive.
Unlike many of the photometer testkits methods out there we use a full colour light meter - most are just a photo diode (one colour) and work on intensity of a single colour (led).
To our knowledge there is no reagent based system or probe that has the resolution we have.
For this reason characterisation was done in raw chemistry by Dr Andrew Mayes head of chemistry at UEA (Andrew is also a sensor expert with many years of experience in industry).
Lots of confusion exists in the market place to do with measuring NH3 and trying to compare the seneye to other methods. An NH3/ NH4 test kit is not going to do this.
Because NH3 has traditional been too hard to accurately measure - especially at low levels it seems to have been largely overlooked in favour of ammonium, TAM, or nitrites.
In our view this is incorrect as ammonia in not just the most toxic substance in the domestic aquarium it's also the first to occur so provides a great early warning system.
pH (on seneye+ slide)
The pH system works in a similar way to NH3 in that is a photo metric reading. The pad for pH has a special coating to protect it over the month and reduced drift.
The downside of this is that it does reduce reaction time (by minutes not hours). Again the original characterisation was done at the UEA.
At the moment we have only a single range pad 6.5 - 9 but we are working on a number of new ones such as low pH pad covering 5 - 7.5 for discus and specialist plants.
The beauty of the system is new pad ranges will be able to be fitted to any existing device.
A note on slides: the life and drift of slides can be compromised by aggressive chemicals in the water especially chlorine / chloramines. The values can be trimmed on the device to match other equipment if the user so wishes however we cannot guarantee the results from third party equipment will be more accurate. We see a large variation between even expensive pH probes when used in low buffered (KH) solutions.
Improvements: The slides come with a unique number and this number will pull a specific algorithm, that calculates the pH and NH3, for that slide as we characterise for different batches. Customers need to be running upto date software to make full advantage of these improvements.
Slide cost: the slide gives you pH and NH3 and if used on line will give you 1500 readings a month on each. There is no need for expensive pH buffers which can introduce inaccuracy or annual replacement of the probe; NH3 cannot be routinely calibrated as the buffers are too unstable (due to off gassing) so replacement of the slide sensor is important. Using the seneye correctly should reduce the need for expensive chemicals.
Water Level
We sense this optically and it also allows us to see if readings are being taken out of water (false positives) this means that no false alarms are created by our server.
Lux
We look at light in a number of ways but all a measured using a specially designed optical chip (all digital hence its size).
Lux is provided as to most people this is an understood measurement and a good bench mark.
Par
The PAR is measured directly by the light sensor and is not a calculation from lux as is often banded around on forums.
If you use the product you will see differences in the two measurements but as they are both quantity measurements in a similar spectral range you would expect them both to rise and fall at a similar rate.
Kelvin K
The device and website will allow kelvin from 3k to 30 k. However with the advent of led lighting it will often report not a kelvin.
We recently published an article about this on our Facebook page please see below.:
"Modern lights will often produce strong coloured lights which are way off the kelvin (K) line in spectrum this line is called the cie planck line (shown as black line above). Light on this line tends to be balanced spectrum with a slight bias to blue (high K) and red (low K)
Once you are above 10k the kelvin quickly shifts up and toward infinity with the addition of only tiny amounts of blue light. This will create a point so far off the line that we have to label it not a kelvin. Also plant tubes often high in green can pull the spectra point away from the line.
Actinic lighting does not have a kelvin; it is a blue coloured (wavelength) lamp and a single tube can add significant amounts of blue which will also give not a kelvin. Seneye looks at the combined light hitting an area i.e. what the plant or coral will receive. The advent of led lights (especially high blue) has made this deviation away from a kelvin much more common.
Hope this helps in your understanding and also helps you understand why we included a 3 point spectra meter on the software to help people see where there light is peaking even when a Kelvin is not present.
We do have some info on the web that is worth a quick read if you want to become the Yoda of aquarium lighting.
http
/www.seneye.com/light/lighting "
Spectra
To complement Kelvin and help when lights are too far off the K line a small spectra graph is shown.
K and spectra are both measurements of quality or fit for purpose.
Calculated NH4
This is the reverse of the calculation used by people to normally work out NH3.
The bad point is that any small inaccuracy in pH temp of ammonia will make the calculated value wrong, whichever way you are working.
This is why we measure toxic NH3 directly, its the only reliable way.
Calculated O2
We mainly included this for the pond guys as they often overlook how much O2 can swing over the year with temperature.
It just acts visual reminder.
Software
All software is constantly being improved and updated with new features being added.
The software resides in the device, on the client computer and on the seneye.me space.
Customers can always find the latest downloads on seneye.com/download
Coming soon
As mentioned before we are working on lots of exciting additions and these can be tracked at
www.seneye.com/coming-soon
A note on the team.
Seneye was formed by a number of experienced fish keepers who have been responsible for some of the greatest innovations in the aquarium market.
I personally have been a professional aquarium filter engineer for 12 years, bringing a microprocessor controlled LED light to the market 7 years ago and over 4 million aquarium filtration units I have designed have been used.
More importantly Ive been a hobbyist for 24 years but unfortunately never found time really get involved in forums guess Ive been too busy inventing!
One of my role was in heavy R&D working with people like the Hanover fish institute to test the performance of aquarium filters with various bio loads.
It was here that I realised what a lack of equipment there was for good affordable aquarium data logging.
We used to have massive issues with drift on probes even with weekly calibration and there were no NH3 probes that could give us the resolution.
Necessity is the mother of invention….etc….
Experience tells me that seneye will eventually be accepted but as with all new technology it will take time.
Matt