Ok so what i have to do now is
1st try to return the fish
2nd ghost feed
3rd check every day fro ammonia?
what happen if there is no ammonia after testing for 1,2 or 3 months?
will be safe for fish then?
IMO since the fish and CUC have already been in the tank a few weeks what is done is done. I would suspect the damsels have done the job for you. It will be kind of hard to tell now how robust of a cycle your tank got. As a result I would not add any fishes for a little while and when you do, do not add to many at once. Check out the stick at the top of the forum called setting up, it full of info. Good luck just my 2 cents.
I would retest your nitrites to make sure you actually have a reading. .25 is a very small amount. Also IMO it doesn't make sense what your readings are. 0 ammonia, .25 nitrite and 0 ammonia just doesn't make much sense.
OK i do that
I go back to my first Q when my nitrites become nitrates cycle is done right?
cause ammonia turned to nitrites, right?
Yes. Nitrites will be zero and remain at zero when cycle is complete