To test water hardness, you need to test your tap water (if it is your source of water) right out of the tap.
Normally the fishless cycling is done when both ammonia and nitrite are at 0ppm for a few days straight while you are still adding a source of ammonia. In your case, I am not clear how many days you have gone without adding fish food. There could be a shortage of ammonia produced by the fish food. Keep adding fish food every day for a few more days, if the ammonia and nitrite both stays at 0ppm then your cycle is indeed done.
When the fishless cycling is truly completed, you may do one (or two) large partial water change to lower the nitrate and get rid of the mess the decaying fish food had made before adding the fish. It is the best to add fish within 24 hours after you have stopped adding a source of ammonia to make sure the good bacteria you have worked so hard to obtain not starving to death.
