that's the best spectrum lamp for macro algae IME, but i have seen folks use all sorts of lamps over their refugiums and the algae grew fine.
the same thing is happening to the tank i maintain at the local gym. after a power outage that killed most of the fish, the macros all died. that was last summer. since then, i've not been able to grow any algae in that refugium. it all withers away.
new fish are in the tank and nutrient levels are high. i also use the reverse lighting schedule, 12 on and 12 off.