There used to be a guy in UT who raised "zot safe" macro in sterile systems, but I think he's no longer doing the whole SH thing.
There's no real way to know about 'droids...the FW dip may work, but I think that a dip long enuff to insure that all of the droids are gone would negatively affect the macro.
You might try doing a SW kalkwasser dip using kalk or pickling lime instead, but even that is no guarantee. All that small live food is perfect for droid blooms, and a single drop of water is enuff to cause problems.