I have a low light non CO2 tank. When I first set it up I was doing the EI method with excel. Then I stopped dosing or doing anything, but I kept up on my water changes. Slowly but surely I was getting some algae. Found out I was doing everything wrong after reading some more and thanks to you guys advice in a previous post... I started dosing excel every other day and my ferts once a week, and I cut back on my water changes to once a month, since I'm dosing the excel.. I bought an API test kit to test for Nitrates to make sure everything was ok. My readings came out to 0 after a month of no water changes. So my question... Are the API test kits reliable? Should I be dosing more KNO3? All the plants look good in my tank except for the rotala has some yellowing and holes on the leaves and my wisteria has some black on the leaves. Other than those 2 plants though, everything looks good and the growth is good. Any suggestions?