We have always been plagued by the question of how best to conserve the water in our Cali so that it will last as long as possible, maintain drinking water quality and not form deposits in the tank and pipes.
After many opinions and little evidence to support the opinions, we decided to test it ourselves and have the water samples analyzed by a laboratory.
First of all, we were not paid by any company for these tests. The analyses are completely financed by us!
What products have we tried?
In our comparison, we wanted to test the two most used preservatives and a device that promises a lot.
The manufacturer writes about the function:
Certec® 3in1 is a preservative product with a preventive effect. It protects drinking water against microbial contamination and inhibits the formation of bio “lm in fresh water systems. The bioelectro-depot ensures that negative ions and bioelectricity are released in a self-regulating manner – automatically with every new tank filling. These negative ions attach themselves to the germs in the water. This inhibits the metabolism, disrupts the formation of new DNA and damages the cell membrane. Instead of forming a colony and multiplying, the bacteria starve to death. The microspherical labyrinth structure of the Certec® 3in1 ceramic resembles an effective surface area of approx. 1050 m#. As bacteria follow chemical and electrical signals to form colonies and prefer the largest colonizable surface, the ceramic acts as an attractor. This creates an attraction effect, which is further strengthened by the negative ions and bioelectricity. Inactivated bacteria are permanently retained in the deep structure and additionally neutralized by the sharp edges of the ceramic.
The manufacturer writes about the function:
In the case of silver, it is the positively charged silver ions that dock onto the microorganisms (e.g. pathogens such as legionella, E. coli etc.) and disrupt the metabolism of the bacteria or lead to cell death in over 30 different mechanisms of action. They act microbially and have a unique long-term effect like no other active ingredient on the market. Products based on chlorine or hydrogen peroxide, for example, cannot be “bound” in water, volatilize and are therefore unsuitable for preservation.
The manufacturer writes about the function:
Tank-O3 fresh water system is a small built-in system for the fresh water tank. Oxygen (O2) is converted into ozone (O3) on the basis of electrolysis. As ozone is an extremely strong, odourless and tasteless oxidizing agent and is not dangerous due to its minimal production, the Tank-O3 fresh water system ensures that the water in the tank and pipes, as well as the fresh water tank itself, remains completely germ-free. Tank-O3 fresh water system kills all bacteria, viruses, fungi and spores and ensures that the water tank remains completely biofilm-free. This is a unique function that no other system can offer.
Test setup
To ensure that all products have the same chances, it was important for us to carry out the tests at the same time.
Tests were carried out in boxes with a capacity of 18 liters. All containers were cleaned, disinfected and filled with the same amount of water from the same source before filling.
After filling, the tested agents were placed in the water according to the instructions and, in the case of tank O3, additionally connected to an external power source.
The picture shows four boxes: So that we had a correct comparison between the test subjects, one box contained under-treated water straight from the tap. This allowed us to evaluate the effectiveness.
After two weeks of standing at a constant temperature, the samples were taken by us and sent to the Raiffeisen Laboratory Rhein-Ahr-Eifel according to instructions.
In the laboratory, the four samples were tested microbiologically and for legionella to determine their suitability as drinking water.
What was analyzed ?
The results of the microbiological examination are interesting for the assessment of whether the water is suitable as drinking water.
The following values were analyzed from all four samples:
– Input temperature
This is the sample temperature on receipt in the laboratory.
– Colony count at 22 °C & 36 °C
The colony count is an indicator of the general microbiological load of the water without any further indication of the presence of pathogens.
In each case, 1 ml of water sample is placed on a culture medium and incubated at 22 °C or 36 °C for 48 hours. The colonies that have developed are counted at 6 – 8x magnification. The incubation temperature gives an indication of the origin of the bacteria. At 22 °C, the majority of germs that occur everywhere in the environment grow, originate from the soil and can form post-germs or slimy coatings in pipes. At 36 °C, heat-loving types of bacteria develop, which indicate putrefaction processes in the soil and possibly faeces. If the colony count at 36 °C incubation temperature is above the limit value, the probability of Legionella occurring is increased.
For both colony counts, the TrwVO has a limit of 100, i.e. a completely germ-free water is not necessary from a health point of view.
– Legionella
Legionella are heat-loving, rod-shaped bacteria that occur in moist soil and fresh water. They cannot survive in salt water. Legionella prefer to multiply between 25 °C and 45 °C. Like other bacteria, legionella adhere to the finest pores/uneven areas of the pipe system and form a biofilm there. They also prefer oily deposits, such as those formed by manganese (e.g. from wells). The growth of biofilms is promoted by nutrients (e.g. in well water), rubber materials (e.g. pull-out kitchen taps), elastomers (e.g. plastic pipes) and silicones. Where water is not heated to a high temperature and is left to stand for long periods of time, they can then multiply en masse in biofilms and become a serious health problem.
Test result
In the end, we were surprised by the result: out of four samples sent in, one failed and was no longer suitable as drinking water after two weeks of standing, but only met the standards for aquarium water. That was quite surprising for us.
Before we go into the results, some information in advance. We filled all the samples in the same way and cleaned the measuring cup between sampling. Contamination can only be caused by the product itself, for whatever reason, for example incorrect storage by the supplier.
The sample from Tank O3 had the lowest contamination and no microbiological impurities at all, followed by untreated tap water, with Certec coming in third place. The only product to fail the test was Silbernetz.
The value of the colony count in the silver mesh was 1043 CFU/ml, as a reminder the limit value is 100 CFU/ml. The laboratory therefore classified this sample as unsuitable for drinking water .
All other samples were absolutely within the normal range and could have been drunk without any problems; biofilm formation was also ruled out at this value.
Each reader can now make a final assessment for themselves, but for us one thing is certain: we won’t be putting any more in our tank! We save the money for additives and prefer to go out to eat.
Download test results
If you are interested and would like to support us with the costs of this test, you can download the detailed laboratory results from our store. With the purchase of the products, this test has cost us over 500 euros, so we would be very happy if one or the other would like to support us in this way. 🙂
