unfortunately im not kidding. by scrubbing out your bio media and using tap water, you pretty much wiped out your whole population of BB and its like starting over everytime. bio media should seldomly need cleaning, and when it does, you should rinse it out in old tank water.
since you only have one fish, the ammonia levels will not rise as rapidly as if it were fully stocked. hopefully the bacteria can grow fast enought to cope with the ammonia levels as they rise and it wont harm your fish. do you have a test kit? start testing your water in a few days and keep an eye on the ammonia levels.
if they start to get too high, start doing water changes every other day to keep the ammonia at safe levels - until your filter re-establishes itself. once your ammonia and nitrites hit 0, you can start with your regular water changes. be sure to treat the water as you've been doing but definately dont clean your filters/gravel with tap water
