I have no idea as to why my 5 year old tank decided to turn all my beautiful live GREEN plants into ones that have a coat of brown algae on them

65 gallon tank with one 6700 T5 bulb and one colormax bulb. I change my water weekly, including substrate cleanings (one side of tank on one week and the opposite side of tank the next) leave me lights on for around 9 hours a day and .

I have live plants; amazon swords, java fern and anubias nana and petite. I dose flourish comprehensive once a week and flourish excel twice a week.

Ammonia is always 0
Nitrites are always 0
Nitrates range from 0-10

This has been going on for at least two months and I have no idea why. Nothing new has been added to the tank with the exception of my Angefish which was added a little over two months ago.

Does anyone have any clue as to what could be wrong or what in the world I can do to get rid of the brown aglae?

Algae is only on plants. Tank glass is crystal clear.

I just want this brown mess gone!