Algae growth in one corner of aquarium?

[HLIB]

Hi pretty new to the forums and fish keeping but here it goes. I've got a 29 gallon heavily planted aquarium that's about 6 months old. Just in the last month I've had a hair algae outbreak on the leaves of my plants which I've slowly been getting rid of with higher co2 levels and less light. But there is green algae in the right corner of the tank in a straight line about 8 inches high and about 10 inches out to the left in the front and all the way to the back of the aquarium on the right side glass. Other than that no green algae on the glass elsewhere. I was thinking maybe a dead zone so I turned the output of the filter a little but no help after 2 weeks it's still strong. Any ideas? Thanks.