Are you feeding a lot? Algae outbreak is often a sign of excess nutrient. I suspect that your bio load/nutrient load and the filtering capacity of your tank are not matched, and excess nutrients (mainly nitrate and phosphate) are accumulating.
Light out treatment will help some, but you need to eliminate the underlying source of your problem. Marine Algae Fix will work for some algae but not for all. For example it will work for some common hair algae but not for Bryopsis. Some people managed to eliminate Bryopsis by raising magnesium level to 1600 ppm or higher.
Since you don't have a lot of coral, you can try a rabbitfish. Some Rabbitfish (especially the spotted kind) are known to nibble on soft corals, but I hear that the majority of them are model citizens. I had one that did not touch any corals except for blue zoanthids. I had to oust him when he started eating my prized blue zoa. The fish left all the other corals including other zoanthids, but he had to go for my blue ones. If you are willing to try a rabbitfish, take some of your algae to an LFS and ask them to give it to a rabbitfish. If the rabbitfish eats them up immediately, you can get it to clean up your tank. When he is done with algae, you can give the fish away or feed them nori or macroalgae. Coral Reef Aquatics usually have a bunch of rabbitfish and they are willing to help you find one that eats your algae. If they happened to have what they call a Teacle snail, you should get it, too. It is a much better algae eater than other snails.
There are some products that bind nitrate or phosphate. Vodka can be used to reduce nitrate and phosphate, but it is tricky and not recommended for beginners.