when i first set up at tank i test frequently for the first 3 months or so

after that i only test when there are issues i can't get to the bottom of, e.g. fish death for unexplained reasons

i'm actually more likely to test tap water than tank as well, i can tell you that my tap water is 7.2pH, kH and gH < 20ppm, 0 nitrite, 0 nitrate but couldn't tell you what any of my tanks are sitting at right now although i know what i'm aiming for in my malawi tank

test kits are essential for setup and issues, otherwise why bother?