Ghost shrimp jump out of the water because:
- The water parameters are unsuitable for them
- They are under stress
- Something is scaring them
Generally, ghost shrimp jump out of the water as a reaction to negative situations. If you notice your shrimp jumping out of the tank, immediately check the water parameters. Ensure the water temperature is appropriate and that there are no ammonia, nitrate, or nitrite spikes.
Also, to prevent stress, provide your ghost shrimp with plenty of plants and hiding spots and avoid housing them with aggressive tankmates.
With that said, some shrimp simply love jumping or climbing out of the tank for no apparent reason. If they do this even though all of their needs are met, you should consider getting a tank cover.
