I don't think an aquarium that has had water in it for only 1 or 2 days should have livestock added to it for a few reasons.
Was this water tested thoroughly to determine if everything was correct? It is debatable that 24 to 48 hour old water has had enough time to stabilize to trust test results. For example, brand new mixed up water typically has the correct ph and Alk but 24 to 48 hours later that may have changed and need adjusted. Are tests being done now? What are the results?
It is typical that newly set up aquariums develops water quality issues (ammonia & nitrite). Hermits may be able to tolerate this buy snails don't deal with it so well.
Cultured / cured live rock is a great idea and will really help with stabilizing the aquarium but I doubt the live rock is going to sustain scavengers for very long. Adding additional food to the tank to compensate for the sterile environment can compound water quality issues.
Has anything been done with the filtration system to inoculate it with nitryfying bacteria?
Because of how small this aquarium is, a very minor problem can easily turn into a huge one. there simply is not enough water volume to dilute water quality issues. And this is the first saltwater aquarium that 213chrisp has done. I think that erroring on the safe side would have been the better way to go.
I'm not saying it cant be done, certainly it can. However, there are a lot of variables that can influence how a cycling aquarium will go. My point was, this tank really is too new / immature to be putting in a clean up crew into it. It would have been better to have aloud the aquarium to go through it's initial cycle or at least given the time to see what the water quality is going to do. There are several things that could(should) have been done to get this tank stable before adding live stock to it and rarely (if ever) is a 1 day old, freshly set up aquarium ready for live stock.
Don't get me wrong, I do think that most of the advise given and the use of good cured rock and ro/di water are great ideas. I just think more time should have passed before livestock was added and that more thorough guidance should have been offered in the beginning.