I WOULD GET AN AQUACLEAR 10 OR 20 DEPENDING ON HOW MUCH FLOW YOUR LOOKIN FOR FOR A TANK THAT SIZE ALL P.H'S IN YOUR RANGE ARE RELITIVLY CHEAP AND SIMILAR IN PRICE AC IS THE BEST THEVE OUT LASTED ALL OTHER BRANDS BY ALOT I WONT BUY ANYTHING BUT AC.
There are lots of power heads to choose from depending on your budget. For a low budget maybe a rio, or a power sweep you can get them as cheap as $12 up to about $25. For a mid price range koralia, seio, eheim, or a maxi jet these all can range anywhere form $25 up to $60. The koralia can be controlled. If you want to be a big spender then go for tunze or a vortech theses are fully controllable and you will not be disappointed with either of these but look to spend anywhere from $75 to $375 per power head.