Sorry, I do have an algae problem and I do have corals. I have a few Zoas, a blasting coral, two mushrooms. They aren’t doing so well.How long has this tank been set up? From what you've posted in this thread, you seem to have some vague ideas about "good" levels of some things (nitrate, phosphate, TDS), but it's unclear if there's really anything wrong with your water. As others have said, in a small tank, especially one with no coral, water changes are usually sufficient to maintain good water quality. No need to even test for magnesium/calcium if all you have in the tank is a clown and an eel.
Just trying to understand what help you really need, if any.