Hi Chelle! I would say after you had a couple of weeks of your nitrites and ammonia reading 0, and your nitrates are low to 0, you should be good to go.
Have fun!!!
PS-glad your LFS gave yoy the proper advice not to add anything-they usually reccomend damsels or some other unfortunate creature...but I have a q...what was LR (cured, uncured) and did you add ANYTHING to start the cycle? Are you sure it even cycled? You added 29 gal exisitng, so you may not have even needed it to cycle.
To be sure, I would add a small amount of fish food (feed the imaginary fish) for the next couple of days, and then take readings again. See if any ammonia. or nitrite show up. But you probably should be fine anyway to start adding soon.