Hello my old tank seems to be getting whits spots on the glass i have never had this before it has been up and running for 5 years. Parameters are fine water chages weekly, 30 gallon tank with 9 fish 1 inch or so in length and 3 ghost shrimp, 6 live plants. I noticed it last week when i did my water change and scrubbed the glass, and it went away, now it is back.