Lemons can be stored in a sealable container and tap water for weeks. Canning jars are particularly suitable for this.
If you don't have such a large jar, you can also use screw-top jars or storage jars for individual fruits. The optimal storage temperature is between zero and nine degrees Celsius for oranges, between one and five degrees Celsius. for tangerines and between ten and 15 degrees Celsius in grapefruits and lemons. The water is changed about every two to three days and can be used well for watering flowers.