[demonsquirt]

In a new setup the canister filter does little to no good. Your reef tank is an actual piece of a large reef system. Many problems take time , months to yrs , to appear and only makes it more confusing by then as you are lead to think it must be something other then your basic setup.

You need good water movement from powerheads. This is what supplys oxygen and controlls PH and algea and keeps your beneficial bacteria at check.
Then Your LR and LS are your best bio filters converting ammonia and nitrate into harmless nitrogen but if flow is low then it only collects these unwanted elements.

For any long term success you need to learn and understand the basics.