The steps sound correct to me. But it may speed up the process if instead you purchase a plastic tub from a hardware store (I like the black industrial ones myself). Having more water does dilute the ammonia and "slows" the amount of water changes you have to do. I think with the current set up you will in fact have to do more water changes. This is just my opinion, but the old saying still holds, "dilution is the solution." That being said I am not the expert here and I hope the ones that are chime in for you.
Best of luck to you!!!!