You will need a skimmer for sure. Lions are messy eaters. You might try a wet/dry if this is going to be a fish only tank, I have heard wet/drys are not good for tanks although I havent experienced any difficulties with them with soft corals. I have also heard but not tried Fluidized Bed Filters, from the few feelers I have put out to evaluate them, everything coming back says they are awesome for FO and FOWLR tanks but not so great for reef tanks. Powerfilters are ok, again, it matters whether this is going to be FO or a reef. I would say go for it. I have a big emperor on my 65 and it does nicely.