It has a small waterfall. It is necessary for water filtration and oxygenation. Especially, if the pond is crowded with many fish.
Of course, the star was
I supose it is a gartner snake: Snake Western Ribbon - Thamnophis proximus ssp.orarius. But I am not very sure.
I feel obliged to note again: Remember, real snakes are wild animals. In any case they are not toys. Nor decorations. Some are very dangerous. Maybe some are not. But do not take the risk. Keep your distance and don't try to play you with them!