Neat design. You could just pop a drain tap in the bottom and then you do not have to disconnect the whole thing to drain out the solids. With an elevated swirl though, you are challenging the pump to get the solids up into the sump. It would be an interesting balancing act of getting the height right to allow the pump to get the swirl going, but not too strong in such a small one, since it could just keep the finer bits in suspension then.