i'm trying to set up 125g reef tank. i have different kinds of corals and fish. i think it's 25x as far as how much flow. however, i was wondering what is the best placement of the powerheads would be in the tank and how many gallons per hour each powerhead should be if i don't want little fish sucked into powerheads and wouldn't drill into corals, but also it wouldn't be like tons of powerheads but reasonable amount. thank you