i have a 46 gallon tank now with about 140 pound live rock running for about 4 month love it i have been running a caister filter and skimmer but what to upgrade to a sump now plus it will hide all the ugly stuff but my real question is if i hook up a sump now all i need is some live sand and rock that will be my filter.do i still need to run the canister filter.thanks for the help jeremy