[Travis]

You have to know which heat/cold packs and how many of them to use based on overnight low temps in your area and at the destination. Unfortunately, this knowledge can only be gained from experience and trial and error. And if you used a delivery service that doesn't guarantee delivery by at least 11am then you are setting yourself up for even more of a risk because you also need to factor in high temps at the destination during the day. If the package made it on time, then it is your fault that the water temp was too low, IMO. In that case I would ship another pack of replacement frags and cover the shipping. If it is something that is the shipping company's fault then I ship a free pack of corals and the buyer covers the shipping.