I have been researching making my own, what type of circulations pump to use and such, as AmRoko suggested. I read many people have great success with their own DIY filter for larger turtles than with expensive ones from stores.I have a bio wheel filter that has been going strong for 16 years now in my tank. But making your own filter is easy, have done that before my self.
I had a hang-on-back filter for a bit with water hyacinth (in the glass tank) but I don't think it did much