Before you go crazy and finish killing everything else, fill a large tote with aged saltwater, (mix a batch and let it sit overnite). Transfer your remaining livestock into the tote with a heater and powerheads to earate the water. Then if you want to rinse everything you can probably do it. However, if you leave your rock out of the water for any extended period of time your bacteria will begin to die off and you will end up with an ammonia spike and a new cycle.
If there is one thing I have learned in this hobby is that there is no problem that panic cannot make worse.
BTW 16ppm Nitrate is now where near high enough to kill anything.