The ready solution is usable for approximately a 6 months when it is stored at room temperature. The water quality and its cleanness level also affect the preservability. If you notice any changes in the solution’s colour, scent or consistency, we recommend you empty the bottle, rinse it thoroughly and prepare another bottle of cleaning spray. The products contain safe, food grade preservatives. Please note that if the cleaner is not used for a longer period of time, little build-up may appear at the bottom of the bottle. This is normal. Shake the bottle before use if build-up has formed. The tablets keep in their packaging for 2 years as long as the packaging stays air and moisture tight.