All of a sudden my 90g bowfront is building up spots of algae. I have had the tank set up for 6 months now and all of a sudden it keeps appearing. I have been using AlgaeFix and following the directions. Once I treat the water I scrape off all excess algae. Only 2 days after treatment it is already re-occuring. Is there anything I can do to prevent this?? What types of fish are great for algae eating?? My set up is a yellow tail bar, hujeta gar, short-body saber, frontosa, golden nugget pleco, and a congo bichir (all range from 3-5in). Thanks a lot for your help and time.