That is very common in new tanks, and the tests are reading zero because the algae is using up the nitrates and phosphates to grow.
You just have to work through this by figuring out where the source of the nitrates/phosphates is coming from, and being diligent about your water chemistry and care of your tank.
So lets start by figuring out where the source of the issue is. Please answer these questions:
How much are you feeding? I'm feeding once daily with flake food
What are you feeding?
How many fish do you have? I currently have 2 clowns 1 angel and a shrimp with snails and hermits
How long do you leave your lights on? I have my aquaticlife running for 12 hoours for antinics and 10 hours for whites
How old are the bulbs? new
How often are you doing water changes? i just did a water change last week which was my first.
How big of a water change are you doing? i did 5 gallons
Are you using tap water? no
What other equipment are you using in your tank (canister filters, protein skimmers, power heads etc?)