I modified my trickle filter on my AR380 by sticking a piece of split plastic tube - I think it was the tube some Aqua Kneedit came in, it is quite thin and about an inch in diameter, and duct taped it along the front to the compartment that houses the filter, so that the water coming out from the filter is deflected towards the back of the tank.
A sponge filter is an airpump driven filter that relies on the movement created by the air to circulate water through the sponge, there are many different types in several shapes and sizes available.