I hear what your saying, just last week I thought of the very same idea. Switching from gravel to local hardware store play sand. I think doing a 100% water change, chloramine the water. some feeder gold fish let them work on cycling your tank, ditch the test strips, get a real kit, watch your levels and youll be ok.
Im far from an expert but Ive raised enough fish and Ive used play sand, on converting sailfin mollies to salt. I put salt in my Oranda tanks also, so keep bumping this thread and youll get a wide variety of info to help ya..