What kind of maintenance does a magnum 350 canister filter require?

i have a 55 gallon saltwater tank running with a 350 along with a biowheel. theres about 60 to 70 pounds of live rock alond with a lionfish, blue tang, snowflake moray, humu trigger, coral beauty, and several others. how often should i change water and how would i go about doing so?What kind of maintenance does a magnum 350 canister filter require?In a 55 gallon, it would need a monthly maintainance of usual cleaning with water.