It's interesting.. many people keep bashing on HOB's (its my first tank ever 3 months in, so I have no true experience to talk on), but the more and more I read, people are having crashes due to their 'full' systems
Pump malfunction, water overflow, etc...
Ya my HOB's aren't the prettiest seeing a 'pipe' stick into the tank (tops are hidden by the canopy), but I'm sure coral will hide that in no time, and in case a power out, I don't have to worry about water leaking everywhere =)
Plus they get the job done, and flow water into the tank. They even help break up the surface to help the lights have that 'shimmer' effect hahaha