I have an EV 180, and have found that it's more than difficult to clean the riser tube (not the cup) when it's time to do so. Mine used to sit in fuge similar to yours with difficult access from the top. Just about got carpal tunnel trying to reach over and around to wipe the inside, and as such, it didn't get cleaned as much as it should have been. I recently bought a used Lifereef skimmer, and have been playing musical skimmers to see which one works best on each tank. 3 skimmers (3rd skimmer is an older ER), 2 tanks. Looks like I'll have to set up another tank before long....
What pump are you running on it?