As mentioned above with cycling and food source. I think the first step for getting them to survive is getting a good source, or at the least making sure they have been at the LFS for close to a week so that the stressed ones can be weaned out. When you do get some be sure to slowly drip acclimate them and keep them in the dark so they don't become too stressed.
Go for it and you will love them in return. Don't be surprised if some don't make it, its all in the distributor for the most part.