Three weeks in to a new tank - high phosphates
I made some big water changes early on and did a 25% a few days ago. No fish or inverts yet. I was unable to test in the beginning so did my tank even cycle? (That's rhetorical I don't expect anyone to answer that). Before my 25% water change a few days ago the nitates and nitrites were 0, ammonia was around .25 and phosphates were 10. Now my ammonia is between 0 and .25 and my phosphates are 9-10. Why the high phosphate readings - decomp of the organic potting soil substrate? I've been using only RO and distilled in my 15G. Never any tap water. And I went so far as to test my water sources and they read 0 phosphates. I have several low light plants including Anubia/Java Fern.