so im at the end of my cycle on my 28 gallon bowfront. im doing partial water changes to lower the nitrates,should i take out the fluval 305 canister filter and clean it?? all it has in it is the little ceramic peices and filter pads. my biological filter is in the live sand,and rock rite? will it help me or hurt me to clean out the canister filter?? also is a sump a must have on a 28 gallon?