Do I have to wash my kefir crystals?

That's a tip you sometimes find on the internet. However, in most cases it is actually more harmful rather than useful to wash your nodules with water, as many of the useful kefir cultures are washed away. If you wash your kefir regularly, you can weaken the culture and probably the diversity of microorganisms will suffer as well. We therefore recommend that you only wash your kefir with water in exceptional with water only in exceptional cases, e.g. if you had cream yeast or slime in the kefir. Otherwise, you can simply sieve off the nodules after each cycle and add them directly to the new mixture.