I had a problem with brown and red algae when i first started to set up my marine tank and it was horrible.
I did some research and realized that there are a couple reason to algae bloom.
1) light
Do not turn on your lights for long period of time 6-8 hrs of white light per day
2) overfeeding
do not over feed your fishes and corals. use a feeding tube when feeding fishes and follow feeding dosage when feeding your corals
3) Phosphate remover
There are a couple product in the market out there to help remove phosphate in your tank. please read and follow the dosage accordingly.
4) Algae removal solution (algae killer)
Make sure you purchase one that if for saltwater use and remove any carbon filters
5)Introduce Algae Eating Animals
i have two turbo sails and a shelly crabs to keep algae at bay.
Well follow some of this step and you will get to get rid of your algae problem in no time.