Algae or Blenny

So I've found myself at a conundrum with my fish tank. I've been battling some wicked algae, byropsis, which is going well. I've dosed some Tech M and have elevated my Mg to over 1800 which it's been for several weeks. Lastly I've been running GFO with my carbon. The battle with the algae is going well, most of it's starting to turn clear.....but...and it's a very big BUT





with all the algae control my Lawnmower blenny no longer as the big fat belly he used to have. He doesn't take well to other prepared foods and he used to have lots of rocks to eat off until the algae took over.





So what do I do? Do I really have to choose between running lots of algae control or keeping a lawnmower blenny?

 

I had tried some green seaweed sheets but no one in the tank ever paid attention to them. Should I try brown instead? Will it make a difference?