I had a new tank going with lots of plants. CO2 and lights, but I did not dose for the first couple weeks. Then I dosed once with Flourish and got a huge outbreak of brown hair algae. Very ugly.
I did large water changes every couple days. I did no more dosing. Cut the lights to very short periods. I ran without lights for 2 days (but that seemed to have little effect). I was planning on just continuing my water change regimen.
Then I added 5 otos. Algae growth seemed to stop. Then it started disappearing at a very rapid rate. And about two weeks after adding the otos, my tank was algae-free.
Could have been many variables... plant growth might have kicked in, water changes may have been helping, who knows what else.... but I really think those otos had something to do with it!
Now I am dosing with the Flourish again, lengthened the light period, and things have been going fine. No signs of algae.