Nice looking setup.
Does the puffer pick at the LR at all? Mine will move around the tank, and will bite the LR, chew it up & spit it back out. That helps keep his beak trimmed.
A word of caution on the sand, if its a small grain like mine. When cleaning with the mag flost it's easy to get some of that black sand in the mag float, and it can scratch the glass. I have several scratches on my 240 from this. It is also a pain to clean the sand from the mag float, as it is black it is hard to see. So be carefull when using the mag float with black sand.