Question on a bio wheel filter

[Gealcath]

Currently i am using a penguin 170 bio wheel in my 15 gallon aquarium. Should i leave or take out the filter cartridges? Also other types of filters are out of the question as thier too big. Also i am not using a protein skimmer as the aquarium is too small to fit one, and i plan on using around a 4" sand bed (Agoronite sand) on the bottom. I only plan on having 1 fish or 1 invert in there, and its going to be fish only (no live corals or other stuff)

[reefpicker]

Hi,

It does not hurt to have them but only if you plan on regularly cleaning the filter pads and replacing the carbon.

How much LR are you placing in the tank? Are you trying to create a deep sand bed (DSB) filter?

I would discard the biowheel. It is not necesary, may increase nitrates on the long run and (the big problem with them), they may splash a lot of salt around the hood.

Just my 2c.