I have a 55 gallon freshwater tank, has been set up for 9 months, and i have been having a lot of algae problems and now i am seeing white spots all of the glass on the inside of the tank, i does not seem to be on the decor, or plants just on the glass, easy to wipe off with a scraper but just really annoying and unatractive, all my parameters are great, no ammonia, nitrites, temp is 78, what is it and how can i get rid of it for good