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How much does it cost?

The Blue Unit is a modular and flexible solution, and as a result not a simple pricing structure.

Blue Unit has several water quality parameters that we measure directly plus several parameters for which we calculate (using internationally recognized techniques). Clients  can either manually pour water samples into the machine; or ideally apply our automatic sampling system. With our automatic sampling system, we can have a single measurement location, or as many as 12 measurement points. With multiple sample points we are then able to automatically calculate some important gradient KPIs, like degasser stripping efficiency, biofilter ammonia removal capacity, fish tank cleaning efficiency, or drumfilter efficiency.

To be able to maximise the useful data to manage a RAS farm (Recirculating Aquaculture System), we normally recommend a 4-point solution for each RAS farm. For example, measurements taken after the Fish tank/s (1), after mechanical filtration (2), after Biofiltration (3), and after Degassing/stripping (4). A client can choose to measure 1 RAS farm (4 measuring points), 2 RAS farms (8 measuring points), or 3 Ras farms (12 measuring points).

The price range for a complete Lab Station with cleaning and automatic sampling system would be between 90.000-135.000 Euros, depending upon the number of measuring points. Smaller units are also available, with modified sensor packages and sampling systems.

We also sell individual analysers like Ammonia, Nitrite and Nitrate where the prices starts from 13.000 Euros

What is the return of Investment (ROI)?

The return of the investment depends on many factors. If you compare our system with having many low-cost sensors around your facility it will take long time to get the payback.

If you consider that our data capture, modelling, visualisation, and support can show you negative trends very early and you can react on them earlier than with alternatives the return of investment will be very low.

Since we have some unique sensors like low level H2S detection and ammonia we can early sense dangerous situations and warn you about lower fish performance and even death. Putting value on these situations gives you a very short return of investment.

Some things to consider is how much time you spend on cleaning and calibrating all your other sensors in the facility. The maintenance is now only on 1 of each measuring type instead of multiple sensors around the whole facility.

Another thing to consider is that do you trust your sensor. If you have 5-6 sensor of same type showing various numbers which one, do you trust?

With 1 sensor per analysis, small changes called drifting often doesn’t make any big difference since what we most look at is gradients. See section about gradients under Q&A here (link). In short, gradients are the measured value before and after an object. With 1 sensor the deviation in the sensor will be the same. With 2 sensor you get 2 deviations and 2 values to keep track of.


What analyses do you make?

H2S – Hydrogen Sulphide

CO2 – Carbon Dioxide

Turbidity -

Temperature - in Degree Celsius

pH -

O2 - Oxygen



TDS -Total Dissolved Solids


NH3 - Ammonia



Particles. Total amount and size distribution. 2-127 microns or 2-750micron models

Total Gas Pressure , TGP

What is Turbidity?

Turbidity is the clearness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye. The measurement of turbidity is a key test of both water clarity and water quality.

Fluids can contain suspended solid matter consisting of particles of many different sizes. Some suspended material will be heavy enough to settle rapidly to the bottom of the container if a liquid sample is left to stand while very small particles will settle only very slowly or not at all if the sample is moving (pumping, aeration). These small solid particles cause the liquid to appear turbid.

How is Turbidity measured?

There are two standard units for measuring and reporting turbidity: Formazin Nephelometric Units (FNU) and Nephelometric Turbidity Units (NTU)

FNU is mostly widely used in Europe, whereas NTU is mostly widely used in the U.S. The ISO 7027 provides the method in water quality for the determination of turbidity. It is used to determine the concentration of suspended particles in a sample of water by measuring the incident light scattered at right angles from the sample. The scattered light is captured by a photodiode, which produces an electronic signal that is converted to a turbidity.

The main difference between NTU and FTU is that NTU measurement uses white light for determination, whereas FTU uses infrared light.

Why is Turbidity so important to follow in RAS?

10 reasons to track turbidity.


Turbidity levels in the biofilter can affect the performance of the beneficial bacteria responsible for converting toxic ammonia and nitrite into nitrate.

High turbidity levels can inhibit the growth and activity of these bacteria, leading to a decrease in water quality and potential fish health issues.

Fish tank:

High turbidity levels in the fish tank can stress the fish and compromise their immune system, making them more susceptible to diseases and parasites.

Monitoring turbidity levels in the fish tank can help identify any sudden changes in water quality, enabling prompt intervention to prevent potential fish health issues.

Mechanical/drum filter:

Turbidity can indicate the effectiveness of mechanical filtration, which removes physical particles from the water column, such as fish waste and uneaten feed.

Monitoring turbidity levels can help identify when the mechanical filter needs cleaning or maintenance to prevent clogging, which can lead to reduced water flow and decreased oxygenation.


Turbidity levels can affect the efficiency of gas transfer in the degasser, which removes excess carbon dioxide and increases oxygen levels in the water.

High turbidity levels can reduce the surface area available for gas exchange, leading to a decrease in oxygenation and potential fish health issues.

Overall water quality:

Turbidity is a critical parameter in monitoring overall water quality, as it is often an indicator of the presence of suspended particles, organic matter, and other contaminants.

Regular monitoring of turbidity levels can help maintain optimal water quality conditions for salmon in RAS systems, leading to healthier fish and increased production efficiency.


In summary, measuring turbidity is an essential aspect of maintaining optimal water quality conditions for salmon in RAS systems, helping to ensure the efficient and sustainable production of high-quality fish.

Is there difference in measured versus calculated values?

Yes. Some of the values we measure together with other measured values or mathematical models inside the sensor come up with calculated values. In theory all values are calculated when you go deep in to measuring and sensor knowledge. We will not cover this fields of expertise here.

At Blue Unit we try to incorporate new and more stable measurements such as rH which has been used in research for a long time. This parameter is calculated based of redox and pH to eliminate the influence of pH on the redox probe.


What analyses don’t you do?

We do not do analyses where the water chemistry changes during transport of the water from the measuring point through pumping to the Lab Station (the measuring device) an example is Total Gas Pressure (TGP). The data from individual sensors can be hooked through our system logged, stored, and visualised alongside with our Lab Station data.

So in short we can do almost any analyses

What is the difference with TDS versus TSS?

Total Dissolved Solids (TDS) varies from Total Suspended Solids (TSS).

An easy explanation is given here:

Total Dissolved Solids (TDS) are the total amount of mobile charged ions, including minerals, salts or metals dissolved in a given volume of water, expressed in units of mg per unit volume of water (mg/L)

Total Suspended Solids (TSS) include all particles suspended in a given volume of water which will not pass through a filter.


Is there much maintenance on your equipment?

Some maintenance and service are required. And even our system is built to last. Everything needs Tender Love and care to work. Even our system is not fault free.

There are 3 types of service and maintenance.

Machine mechanical maintenance and Calibration of sensors. Fault of equipment

Let us start with faults first since that is what happens less.

There are few mechanical parts in The Lab Station and Pump Station. What we see can fail is solenoid valves and small leakages on pipes. We supply spare parts and changing small part is often done by the client in a few hours. We have made demonstration videos of maintenance that are available on our web page when you log in to our system as user. We also provide telephone support on these small repairs.

Mechanical maintenance depends on how clean your water is. If you got very dirty water the membranes used in our gas measurements get clogged. With dirty water we see changing of every 3-4 weeks. Some places the turbidity cup needs to be cleaned at the same time. Expect 1 hour on this job.

Calibration: You should expect to use 1-1,5 hours every month checking that your sensors are calibrated

We are constantly looking for better ways of making our machine, so maintenance gets less and less.

One of our targets are more smart sensors that tells us when to calibrate. We are looking forward to present these.

Some sensors that need only calibration every 12 months we supply new calibrated from our offices. This means changing sensor and returning the used for reuse or safe disposal.

Can the hoses from the Pumps Stations plug or break?

Plugging of hoses due to particles we have not experienced. The reason is that we have mesh filters in front of the pump’s inlet to avoid blockage. We also blow the inlet and the filter so any particle that might be on the mesh is blown away.

Breakage of hoses we have seen. This has not been due to poor quality or age but more that the clients have ran in to unprotected hoses with various equipment. Luckily repairing a broken hose is easy by putting in a new section of hose replacing the broken.

We see that a few times we need to tighten the clamps in the end of the hoses to avoid leak. This is done with normal tools during maintenance rounds at the farm.


How do you do the calibration?

The monthly calibration is done by the clients after standard methods in the industry and recommended by the sensor supplier. Videos and user manuals are made available, so you know how to do it.

Yearly calibration can be done by Blue Unit as a part of a service of we send already calibrated sensors from our offices to you. You change the sensors we check them online for you and you return the used sensor for our recalibration or safe disposal.


How many systems have you sold?

In total we have pr January 2023 sold 26 units. Some of these are model 0,5 and 1. Some of these are taken out because of age and outdated technology. Some of the fish farms we have supplied to have also stopped. Today we monitor 18 RAS units around the globe.


Can we rent a system?

Yes. We offer rental solutions for longer and shorter periods.


Can we test a system for free?

Unfortunately, No. We do have systems for shorter time, 6 months rental.


Why should I buy one?

If you want to optimise your plant performance Blue Unit lab Station can be the solution.

Let us give you some examples of practical use.

Saving fish:

If you slowly get changes in water quality over time, we can pick up this change early and warn you. This will lead to faster response to make changes and less effect on your fish. Our Ammonia and H2S sensors tell you and early warns you about critical and life threatening situations that can occur.

Saving Feed:

Lab Station through several parameters can easily pick up overfeeding and poor feed quality. Changing these parameters saves you money.

Saving energy:

By knowing your water quality through your facility you can know what to turn down and not overuse. Energy, chemicals, labour are examples.

Save resources:

Skilled people should be used for other things than look in to water chemistry. Let us free up you people’s time.

Fish Welfare:

When a fish has good conditions from water quality, is healthy and are fed right feed at right amounts of feed the conditions are optimal for maximal health, growth and profit.


Logging and documentation of water quality towards the authority and client can also be required or wanted. Blue unit can compile and deliver documentation for you to show to the various stakeholders. Typical example is CO2 level over a long time. This is large data amounts that we can help on reporting and visualise for you.



What can go wrong?

Our system is mainly not the security system on your facility. It is as optimising and plant performance tool. So, if you rely on it as a security system caution should be taken.

With the high values and risks at stake on a fish farm or well boat several alarm systems should be used.


Is your data securely stored?

Yes. Our data is stored in common well-known databases like Azure from Microsoft.

We create secure bridge of data transfer from our Lab Station to the Cloud and to you as user when you log on to the web visualisation page.

Cybersecurity is very important for us. Our log in is 2 factorials if necessary.


Can I get data to my own Scada system?

Yes. You can read raw data from our Lab Station directly to your Scada. This though has extra costs to set up. Both from our side and you Scada supplier.


Do you generate alarms?

Yes, we generate alarms. These alarms are from raw data values but also from models. These can be sent to the clients as Emails or SMS. By fetching our raw data from Lab Station, you can set up alarms in your Scada system for your own surveillance and logging.


Who makes the models?

Our Biologists makes the models. They got modelling experience, knows farming and water chemistry and knows what to look for. These are also the same persons giving you personal support during training and follow up services.

Do you make models or only raw data?

One of our strengths is that we can do both. The way we store data means we can continuously show model data and raw data at the same views.


Who is your competitor?

In general, we compete with sensors from various suppliers been placed around on the farm and connected directly to the farms Scada system. There are also several suppliers of solutions where you have sensor connection points with example 4-5 sensors in one connector box and communicating the data via Wi-Fi or Cable to the cloud and web view.

As we are now and up to today, we do not know of any other company doing it the same way we do it. We are unique since we pump water from a sample point into a centralised unit where we analyse the water samples.

It must be mentioned that we are not a sensor supplier but a system supplier. The total package with centralised sensors, advanced visualisation, historic data storage, modelling, and the customised personal support we supply is a unique service.


How long does the machine last?

We have machines in operation that are over 7 years old. We expect them to last long. Some things that are out of our hands includes availability on critical components. This is always a risk with today’s situation. However, we are constantly looking for alternative suppliers to be able to rebuild older machines to make them last even longer. Another thing to mention is that the development is going so fast with new sensors etc., so at some point it doesn’t make sense to rebuild anymore but rather get the latest model.


What is the benefit of a centralised system?

The benefits are many.

There are less sensors to maintain and that can fail. Our sensors are not in a rough environment like inside a filter of in the fish tank. Our water sample is collected by pumps well protected by HDPE plastic the pumps are either inside the rough environment or can be put outside and having a small tube in to the environment. Our pumps, pipes and sensors are automatically cleaned every 2-3 nights to be kept free of biofouling. Sensors hanging in the water around a facility must be cleaned frequent to work optimal.

The use of fewer sensors make us be able to use different sensor often more expensive sensors. The extra cost is justified with that you only need one sensor.

Time for calibration. Less maintenance time is used when you have 1 sensor versus many sensors of same type around the farm.

Some of the sensors we use cannot be placed around the facility and need to be placed in a safe compartment (the Lab Station) this is since these sensors need a certain protected environment and cannot be out where there is splash, temperature changes, vibration etc.


What are the negatives of a centralised analyse system ?

The initial investment can be too high for many companies.

If you have a small, flow through, easy to overview farm it can be hard to justify the investment.

If you need very quick answer to you analyses as a manual probe gives, then we cannot do our measurement quicker than in 5 minutes intervals. This is due to the fact of pumping, cleaning, and pumping the new sample back into the lab Station takes 5 minutes. The longer analyses where we do sample preparation in the Lab Station can take up to 15 minutes. So, on H2S and Co2 we are working in 15 minutes intervals. Our experience is that this resolution is good enough for RAS farms but still it is a limitation.

If one of our more expensive sensors breaks. The delivery time and installation time on these can be longer than just sending a new probe.

Since we are mowing the water, we cannot measure Total Gas Pressure (TGP). If this is needed, we can couple in sensors measuring directly to the location. This will be a special build. You will then get the data in to same visualisation platform.


Do you have any patents?

Yes, we have 2 main patents that we hold in several countries in the world.

One patent is for the Lab System itself and one patent is for our CO2 sensor.


What is a gradient?

Shortly put: a gradient is the difference in a measured value before and after a part of a Recirculation Aquaculture Farm (RAS). Example in a Biofilter we measure several water parameters before and after. So, if you CO2 level has a certain value before the biofilter and when we measure higher or lower value after the filter this can give indication of a cause and performance of this unit. When we calculate the changes over the biofilter we can compare different biofilters over time and the gradients will show an overall performance of our farms various equipment compared the how we run the components and the fish and feed load involved.


What is SaaS on your solution?

Software as a service is a software and delivery model that involves licensing out software as a subscription for use by others. In Blue Unit this means an Operating Agreement. But the Operating agreement is also so much more than SaaS. Please read the Q&A section about Operating Agreement.  SaaS a service usually means that the person behind it hosts the service. Advantages are that the software is always updated, and new functions are added continuously. Disadvantages are that you often need an internet connection. We see that most of our clients have sites with good internet access.

We also believe the safe storage and Cyber security is important.


Is there an alternative to SaaS for your solution?

No. We believe that SaaS is the future and the best solution for our business and you as a client.

Why is that?

In the old days updating software meant traveling and doing the changes physically on a location. This was time consuming and expensive. Then the technology advanced and we could do changes remotely on each individual unit. Now we can make a new model or visualisation and distribute much easier, safer and to a lower cost for our clients.


What if my Internet fails?

In the cases we are afraid of internet failing we can supply an internal storage of data on a SD card. This solution mean that your data will be uploaded again when the Internet is up and working. This solution does mean that you don’t lose your data.

The lab Station only needs Internet for the cloud / web service. The Lab Station will continue taking and analysing its samples without internet.

In those cases where we as an example use H2S gas as an alarm we take the signals directly from the Lab Station to your Scada system and this function is not dependent on internet.

Our system is often used in optimising a plants performance, so a short loss of data is normally not an issue.


Are you a sensor supplier?

Yes and No. in the sense of supplying single sensor we are not. We choose the sensors we believe are best for our clients, test them under real conditions over longer periods and put them together as a package that we include in our centralised system.


How do you choose your sensors?

We choose our sensors and from various criteria. The main criteria are.





Our system allows us to include more expensive sensor since we only use 1 set instead of when you have a decentralised system and need multiple sensors of each type.


How do you test your sensors?

We are so lucky that we have access to a test farm where we continuous validate our new and existing sensor under real conditions. We also test various sensors with some or our clients.


What sensors do you use?

All our sensors come from known brands.

Sometimes we buy and relabel sensors to our own brand. This is in good cooperation with the manufacturer. Our CO2 sensor that is developed by us and patented is made by for us by a sensor manufacturer.


What is an Operating Agreement?

An Operational Agreement is necessary for you to be able to use your Lab Station.

The service we provide does have a cost that we share among all users but also cost for individual adaptions for your need. Therefore, the cost varies.

An operational agreement includes. A certain amount of support that we agree on during the sales process. Personal service, online or phone. Adaptions and re-adaptions to your facilities need. Web access. Web visualisation. Access to our existing and new models. Safe storage, function checks (online) and more.


Can I use the machine without an Operating Agreement?

The short answer is no. Since the data transfer, safe storage, models, and calculations are done in the Cloud, Blue unit has cost every month for having the people and a reliable safe cloud solution. These costs are client dependent but also there are some common costs.


What does an Operating Agreement cost?

The price for an Operational Agreement varies a lot. It can be from 500-2000 Euros per month.

The price depends on the size of the system, how much support and service you need.

Very often we see that in the first year the user/client needs more support and then the price is higher since our technicians and biologist are involved with, training, setups, organising and helping on data understanding.


Do you have Licences?

Yes and no. Our operating agreement was earlier called a license or subscription.

Now we call it operational agreement since we believe that is more what it is. Please read the Q&A about operational agreement here (link).


What does the Parameters mean?

H2S (Hydrogen sulfide):

H2S is a toxic gas that can cause kill fish even at relatively low concentrations. In aquaculture, it is essential to monitor H2S levels to prevent fish mortality. We use specialized equipment that can monitor very small changes of H2S concentration. H2S is made naturally in the system by decomposing matter such as faeces, but also in the biofilter when the bacteria remove other harmful components in the water. This is measured as µg/L but is also often seen as ppmv or ppm.

CO2 (Carbon dioxide):

CO2 is a natural by-product from the fish respiration. However, high levels of CO2 can cause harm and can negatively impact water quality. This is partly because that in the water, a portion of the CO2 is being converted into carbonic acid. CO2 levels should be kept low to ensure optimal fish health and growth. By monitoring CO2 levels, aquaculture professionals can maintain optimal water quality and create a healthy environment for fish.

TIC (Total Inorganic Carbon):

This measurement detects the amount of carbon in the water that isn’t bound as organic matter such as faeces or food. It is also by many used interchangeably for alkalinity and can to a great extend be interpreted as such. Alkalinity is a measure of how resistant the water is to pH changes so keeping this a too low levels can lead to unstable water quality which can be detrimental for the fish. Normal ranged for alkalinity in fish farming is between 70-200 mg/L depending on many factors such as if the farm is using fresh- or marine water.

NH3 (Ammonia):

Ammonia is naturally produced as a waste product from the fish but can be toxic for the fish themselves at higher concentrations. In fish farming then ammonia is removed from the system via the biofilter than converts it into nitrate and nitrite. Typical safe levels is below 0.5-1 mg/L.


How is the Lab station connected to your cloud solution?
Lab Station is connected to Cloud either by
Internet cabling or by a Secomea modem.

Which protocol/setup is used to secure this internet connection?
Data is exchanged with the web server by the http-protocol (port 80).
When there is a data exchange between Lab Station and Cloud first
thing is to exchange a key to verify the identity of the ingoing data.

Where is your server located and who serves this system?
Today the server is located in Microsoft Environment.