I have a 150 5x2x2 with a similiar setup as your. I run two eheim 2028 canisters and an Emp400 HOB filter. I only clean my canisters once every 6 months. I do biweekly maintaince emptying out the filter floss in the Emperor. I don't run carbon unless the tank wreaks from uneaten spoiled food. My water is normally clear enough to be acceptable by most fish keeping standards but I am such very anal with clear water. I noticed my water was not as clear when my UV bulb got burned out. Once I replaced the bulb the UV took the clarity to a new level. People don't give UV the credits they're capable of doing. Most people bashing on UV on freshwater either want to penny pinch or have never used a UV. If you can afford a UV then definitely go for it.