I ream the luer tip out of a 30cc Luer Lok syringe & put some tubing on the end. You could also buy a small, cheap gravel vac & cut some off the end of the vac's length.
routing your vac through the filter would screen out solids sure, but what about trates? u know, the main reason for water changes...u could do that but u should still do a water change about 30% at the same time, when u have ur old tank water in a bucket, slosh ur filter around in it to get rid of the solid garbage, dont rinse it in tap water because u will lose a lot of ur good bacterias. the key is to get fresh water in there, even if your tank looks like crap you still need good params. dont forget the de-chlor!
I use a turkey baster in bare bottom nano tanks. For anything smaller then a nano?? I make a siphon out of a piece of plastic and airline tubing.. hardwork, but efficient.