I guess you're lucky that your fish store even knows what cycling is...let alone the best way to do it. Take the Nutrafin Cycle back. It's not useless (it helps prepare a good environment for bacteria to get started) but it doesn't provide the bacteria you need. If you want to gert bottled bacteria, I suggest these: Tetra Safstart is easy to find, but must be fresh (check the sell-by date) and never have been exposed to heat or cold. Most of the time it's OK. Same with ATM Colony, API Quickstart or Niteout. Seachem Stabikity has worked for some keepers. Arguably the best (and most expensive) is Dr Tim's One-and-Only, shipped fresh from the factory in an insulated container to ensure freshness and viability.
These produsct were designed to promote fish-in cycling, using the fish as an ammonia source. If you're cycling for a sorority, I'd suggest fishless cycling, using pure ammonia in order to develop a large bacteria colony to accommodate the large bioload of a sorority which should be stocked all at once. You can buy "pure" ammonia at Ace Hardware (Janitorial strength) or online from Dr Tim (on Amazon, Dr Foster and Smith, etc.), kind of expensive.
Buying a sorority whose members are already used to each other and have already established a hierarchy is a great way to go. Saves you QT time and pecking order time and stress.