Fluval Edge Reef Saltwater Aquascape

[@pashazero]

Here is my Fluval Edge 6 Gal. I have a couple questions. 1. I have the 50w jager heater but as you can see from the video it is very obtrusive in the tank. Can i hide it under the sand? Is there any better heaters that are less obtrusive? I live in michigan so I need something that will last a winter. 2. How is my aquascaping? 3. How is the position of the power head koralia? Its a koralia nano 250. Should i point it into the rocks?