but if you keep removing what you can when ever you can and keep starving your bound to win
i think you have enough flow for your tank more flow wont hurt but your not lacking either
gfo is great i run it all the time i would never run a tank without it now its amazing what it does b y its self alone.
rowaphos to my knowlege is a type of gfo, but it works better in a reactor in a tank as large as a 180g you need to run it through a reactor.
a cheap reactor is very easy to build google "gatorade reactor" i built one and it worked great on a small tank.reactors are cheap though you could get one for $30-50