Pour water, lemon juice, vinegar, whine, liquor or kernel oil in two glasses: Put one of the glasses on the aqua blue device, the other one at least 2 metres away from it.
After 5 minutes, try the treated water first and then the untreated water.
Alternative: Pour water into a jar before installation of aqua blue and half an hour after installation and compare the taste
Make the aqua blue water and untreated (of your neighbour without water treatment) water boil in two similar pots at the same time and then turn it off.
Watch how different both of waters are (opacities, lime deposit, gas bubbles). Empty the pots and compare the deposits right after drying.
Long-time freshness test
Put in aqua blue water and untreated water in two similar glasses under the same conditions (distance >2m) and let them be for a few (4 – 8) weeks and observe (colour, opacities, smell, scale rings).
Pour tap water before installation and half an hour after installation of aqua blue into a snow-white bucket (20 litres) each and compare the colour and clarity.
Alternative: Fill a bathtub with normal and afterwards with aqua blue water (20 cm) and compare the appearance (colour, clarity)