Lawnmower blenny

So, I have a small hair algae problem in my 14 gallon reef and decided to add a lawnmower blenny to help seeing as how they love to eat hair algae. Problem is, he/she is not eating and of the algae? the fish is an awesome edition to the tank but like I said, he's not really eating any algae like I'd hoped he would. Also, he doesn't eat the food when I feed the tank either. It's been about 2 weeks since I added him.