i have a fluval 404, a rena xp3, a few magnums, ac 500s, ect. looking at all of the designs i would say that the fluval has the worst design. the water goes down through foam and then up the sides of all of the media cartridges. there is actually a raised peice of plastic preventing the water from making into the bottom media cartridge. on others like the xp3 the water is forced to go through.
lastly you could use a smaller filter on a 30 gallon but more filteration won't hurt.
i use a fluval404 full blast on an octagon 27 gallon tank
lastly you could use a smaller filter on a 30 gallon but more filteration won't hurt.
i use a fluval404 full blast on an octagon 27 gallon tank