Why do my guppies keep disappearing I only have guppies in your tank?

If your guppies keep disappearing and there are no other fish in the tank, it's possible they are hiding due to stress or environmental factors. Check for any decorations, plants, or substrate where they might be getting trapped or hiding. Additionally, ensure that the water parameters are suitable, as poor water quality can lead to unusual behavior. It's also worth considering that if the tank is small, they may be more prone to stress and hiding.