Never QT'd before. need advice.

Ich can survive up to 8 weeks (the most resistant strains) without a host. If you want it done faster, simply bleach the material, rinse/dechlor it well, let it dry, then place it back on the main tank to recolonize for next time.
 
I was going by this. It says 1-2 days as a free swimming tomite before they die if no host is found
 
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