In a properly cycled tank, healthy for fish, ammonia and nitrites should be zero, and nitrates 0-20.
Are you using a liquid test kit or dip strips. The strips are not reliable.
If you really have 10 ppm of ammonia, you need to do water changes until it indicates zero.
What are the same readings on your tap water?
How long have you had fish in this tank? Just set it up?