It may help but won't do it by itself. You need to find the source of the food for the algae and reduce or eliminate it. First things i would look at would be phosphates and nitrates in the water or from feeding.
How is it stocked? Is your bio load too high for a pico? Does it get any direct sunlight? How long has it been set up, GHA can be a natural part of the maturing process. Do you have any snails you could dump in even temporarily?
I have one little goby in it and a small CUC, the rest is coral. I have nitrate media in my HOB filter, so I am assuming its a phosphate problem (need to test). I have been using Algaefix Marine and it seems to be helping, but I think my next move is to remove the rock and scrub it...and start over.
You might try something like Chemipure Elite, I understand it has granular ferric oxide, a phosphate removal media in its mixture. Otherwise a little GFO like Phosban in a small filter bag in your HOB might help. It does not take much even for a large system, only 150 grams in a 100G tank so it will last you a long time in a pico.