I agree with what others have said, go with a moving bed. Very easy to build, self cleaning and proven to work.
Best media choices would be
Kaldnes or
Bioflow 9
Important note you need to have adequant mechanical filtration before your moving bed.
Here is a simple upflow mechanical filter I built for my QT using a piece of rolled matala:
From the mechanical filter water flows to a moving bed. Moving bed consists of an inlet and outlet screen so media stays in the chamber, a drain (not pictured), some air stones and media.
