Hi,
I have a 75, too, filtered with only two canisters and live rock and a HOB protein skimmer (is that an aqua C I see?? I have mine hanging in the exact same place, if it is). But it looks like you have a nice pre-drilled tank and everything. Can I ask you what you've got the Fluval for?
BTW, nice tank!! Oh and another BTW, I have a regal tang in my 75 who is fat and sassy. It's great, every time I feed, after dinner, it starts playing with bubbles, get the chromis in on it, too.
Joy