Yeah the API master kit is definitely worth the investment.
You might want to look at getting some live plants too, whilst your tank is cycling, aka building up the 'beneficial bacteria' these will absorb a lot, if not all, the ammonia and nitrites and use them to grow etc. A floating one like water sprite is ideal in your situation as requires pretty much zero maintenance yet is super absorbent.
As per your water changes..........whilst not using a conditioner, as much good as they are doing at removing nitrates or what not, they are also very counter productive whilst not using a conditioner. Adding water that contains chloramine/chlorine/both will kill off any of the 'beneficial bacteria' in your tank and is VERY harmful to your fish. Chlorine will actually burn off the gill filaments disabling the ability to get oxygen, leading to eventual death by asphyxiation.
You can look up what your water contains on their website, by law it is public knowledge.
IF its just chlorine - as stated this will actually ''off gas'' if left, say, in a buvket over night...then used for the water change.
BUT if your water also contains chloramine, which a lot do nowadays, then this cant be removed the same way and MUST be treated with a dechlorinater..... the preferred option being seachem prime (which will also detoxify the ammonia and nitrites in your water for 24-48 hours)
Hope this helps