Not going to play in the QT or no QT sand bed however if you are doing fresh water dips or baths (yes, they are different) please check out Bob Fenner's "Dips/Baths, A Useful Protocol for Excluding Many External Fish Parasites" article on Wet Web Media. Specifically pay attention to Methylene blue. Takes freshwater dips to a whole new level for both fish and hobbyist by reducing stress to both parties
If I was to put another CBB into my display my first priority would be to find one locally so I can visually inspect. If not local then via online source with similar access (email photos). Check weather if shipping and plan accordingly then purchase. Next day/morning prep 2 x RO/DI water buckets, match ph, add Methylene blue to 1, room temp, equalize CBB, timer, and bath begins. During bath checking CBB frequently through the first 15 minutes. If fish is doing well decide if I want to run to 30 minute bath or stop at 15. Once dip/bath is done using a gloved hand gently remove CBB and rinse in 2nd RO/DI bucket and then place into display with lights out.
TL;DR: To quote Mr. Fenner: "Methylene blue is a good oxygenating dye, sort of like our blood's hemoglobin, aiding in keeping oxygen concentration high".