good fuge gone bad

I have a 60g tank retrofited to act as a refugium and sump for my 100g
display tank. The fuge side holds somewhere around 30g, has a DSB, some
live rock, and a small clean up crew. It's running reverse photocycle
to the display. I've been grown calupera, cheato and some other twiggy
macro quite well for the 8 months the tank has been up. Slowly, over
the past month or so, green hair algae has started to grow in the fuge.
Now the whole idea is that the macro algae is able to out compete the
nuisance algae like the green hair, right? The fuge is lit by some
random screw in 28w CF and a 20w corallife 50/50. Any idea what is
going on? Should I be testing for something specific or look at
something more obvious like degraded light output or shifting spectrum
making more favorable conditions for the green hair to grow?


-K