so im deff not a beginner but the more and more i read up on articles about nitrate levels the more and more i keep seeing diff information about the level it should be in the aquarium. my levels have always read 40ppm and thats where they stay. my question is....is 40ppm bad? my fish are fine and i havent lost a fish since right after i started a little over 2 years ago when i really didnt know what i was doing. i need to know if my nitrate level is high or is fine. thanks!

40 ppm is fine for most fish

optimally between 20 to 40 ppm...live plants will help keep the nitrate levels down for they use nitrates as food/starches

if the nitrate reads at a steady 50 to 80 ppm, this level will stress the fish

over 80 ppm it is toxic

so at 40 ppm, you are fine