that is why I said if things are set up right with the proper lighting, bedding, water changes, etc...I had tanks before for years..never a problem mr. test kit. Obviously you check the spec. gravity when you do water additions and add salt accordingly. You have proper mechanical and biological filtration, etc.etc..
...don't buy into the pet supplies industry so easily..they are always ready and waiting to sell, sell, sell and put the fear of god in you if you don't use their new and improved product . Leaving things to cycle naturally with the proper substrates and NOT over crowding your tank with fishes that pollute and set off the chemistry is key...no one uses a 'test kit' on the great barrier reef last I heard...Mainly, my personal opinion is to just let the tank cycle for 6 weeks when it's new and don't add fish. Just be patient. I got my 3 dollar fish, but like I said, it would be no great risk, I've done it before, but if you're going to get expensive creatures, just wait 6 weeks and let it cycle naturally.