I know about the pH and the temperature but idk about the nitrates, nitrites and the other stuff.
Ammonia and nitrite must be 0, same for all fish and inverts. Nitrates must be no more than 20 ppm.
Ammonia and Nitrite is the bad stuff so keep it at 0, nitrate lower the better fixed*
Nitrites are toxic to fish and should be kept at 0 ppm. 0 ppm nitrate means you're tank is not cycled unless your tank is very lightly stocked or a heavily planted tank. Having a bit of nitrates should do no harm. You're right on the ammonia though.
yeah I got all terms backwards
Are you familiar with the nitrogen cycle? (click the word, it's a link). Browse through the many helpful stickies on this forum to understand what they are and why they're important.