Planning my 30 Gallon build

[Rivercats]

You can try cutting back to 8 hours but when algae becomes an issue only running lights 6 hours really helps. It kind of sounds like it could be BBA. You can spot treat it will Excel or H2O2 (hydrogen peroxide 3%). Just pull up 1ml of Excel or Peroxide per 5 gallons of tank water in a needless syringe and get real close to the algae and slowly squit the Excel or Peroxide on the algae. Now if you use Peroxide you need to turn your tank lights and filters off for 15 minutes. You don't have to do that with Excel.