This comes down to what you want to keep in the way of corals and clams. Both of these require large amounts of light.
If you are not going to keep corals or clams, the easiest way to control algae is to greatly reduce the light. Fish only need enough to see to eat their food.
If you are going to keep corals or clams, your going to need to do a lot more work. In this case, you must control nitrates and phosphates. In other words, you must remove them, one way or another at a rate greater than they enter the system.
Here are possible sources of nitrates and phosphates -
Feeding, especially flake food and not rinsing frozen foods before feeding.
Using tap water to mix salt. Always use RO/DI water for this.
"Dirt traps" and "nitrate factories" in the system.
Low quality carbon can leach nutrients.
Low quality salt can sometimes add nutrients. This is unusual today.
Here are possible ways to remove nitrates and phosphates -
Water changes. Change 1/2 the water and you reduce the nutrients by 1/2.
Skimming. Remove the waste products before the biological filtration need to break then down.
Nitrate and phosphate removal products.
Deep sand beds.
Each of these has advantages and disadvantages. Most people that control algae well use many of the above methods.
There are also other items that can effect algae growth rates.
Good clean up crew.
Other livestock that eats algae.
Low general water quality, especially when the readings are off.
Lighting, sometimes you can reduce it, especially in FO or FOWLR systems.
Old light bulbs. Colors change as they age and this can be a factor.
Water flow. More flow will often help keep algae down.
Manual removal. Very important, especially when there is a big problem.
Generally I consider it a mistake to use algaecides or cyano treatments. While they might kill the one problem algae, unless you fix the underlying problems, you will simply get regrowth of another unwanted algae.