My 75 gallon has finally cycled! Ammonia and Nitrites are processing to 0 ppm within 24 hours of pure ammonia being added at 3 ppm. I am going to start adding fish hopefully tomorrow. I was curious and tested my nitrates just to see what they were at before doing the expected 90% water change as per the fishless cycle instructions, and they were at 0 ppm. They were at 20 ppm a couple days ago before I added a couple bunches of hornwort and one more large water hyacinth. My question is: do plants (particularly hornwort and water hyacinth) suck up that much nitrates? I've read a lot of differing views as to how effective plants in general are at keeping nitrates down. I know they are not replacements for regular water changes and good filtration, I'm just curious.