He's a lovely little sub-dues fella. I also have nothing but praise for those arcadia arc tanks. Well worth what i consider to be a small price ag for such an attractive tank.
Love him, and the tank! Your water changes and cleaning would be easier if you left your tank without gravel. I'm trying to figure out how to make my dividers stay in place without a substrate or siliconing them ATM so I can remove mine.
It depends on the type of sand. If it's a larger, heavier grain sand, you can just vacuum it like regular gravel, but if it's smaller finer sand, you have to hover over the graves to avoid sucking it up, which can be quite annoying.