W/out live rock, or a wet/dry where is the benefical bacteria to live? (besides the sides of your tank).
Live rock, live sand, wet/dry filters all provide surface area for denitrifiyng bacteria to colonize adn work. I guess dependin on your bioload, your water paramters would eithe rget better or worse. Small bioloads could proly do Okay w/out any LR/LS, while a higher bioload tank would suffer.
So.... whats your current stocking plan?