Hello; Algae is common in tanks. If you are not planning to grow live plants, the simplest way to limit algae may be to keep the light off most of the time. There are other ways reported.
tanning is a common technique to push up arowana color by putting lights that contains uv a and uv b for a long hour. some people do 3/6/8/12/24 hrs interval.. and ive been doin 24hours for 5 days non stop top tanning..
top tanning as the name it self is by placinh the light on top of the tank.
there is side tanning where people put the lihht on the side of the tank
^ running that light 24hrs a day / 5 days a week will definitely cause algae... but at least doesnt look too crazy, just clean it out with weekly water changes...
Maybe a pleco, or bait fish minnows. Will eat it.
Their is some algae gone, products for sale, not sure on the dangers on fish.
I encourage algae to grow in my tanks. It is one of those things, if you can't beat it, join it.