I'm glad we're on the same page.......incidentally I happened to just be reading this
in another thread and that was said by the creator of the almighty chart, not some smart a$$ cat
For me, I had bba bad about a month into my experience, it smothered all my plants and hardscape. I added pressurized co2 and began dosing and it mostly went away, it's no longer on any plants... however I can't get it off of the hardscape directly under the light.....thinking of adding screen to cut light on hardscape areas..........
It may be a flow issue, but if it is bba, try co2 first imo.. but you say brown algae.......to me, this usually means diatoms, can you rub it off with your fingers? if not, then you are right its bba, but if you can rub it off, it's likely diatoms so I would try to simply increase light and continue to keep clean water and see if that helps
edit: I don't mean to make it sound like low light is a bad thing....in fact its quite the opposite sometimes........
sorry for the ramble
edit x2: oh yeah I said I wouldn't speculate on what is causing or what to do! whoops