Question about using a spong filter in QT

[Deep Reef]

I had a fish I did the TT method with and after was placed into the qt tank for final observation. after a week he died with no visible disease. I am cleaning the tanks with bleach and freshwater. should i throw the sponge filter out or could I also clean that with bleach and freshwater? just wondering as they are sometimes difficult to find locally.

 

[MrTuskfish]

I use an AquaClear HOB filter. The sponges are dirt cheap when bought by the dozen online. I haven't bought anything at a LFS in years. I'm sure it can be done, but I just don't trust cleaning sponge filter material.