Buy the size box you want, then buy styro foam from home depot, cut to size, to make your own insulated box. I individually bag each coral. I put all corals into a bag, then seal, then add another bag. I like triple bagging. Add corals into box, I add news paper around bag to make sure there is no movement inside box. I then use a 48 hour reptile hear pack. Depending on where its going I will cut heat pack in half, to keep from getting to warm. I wrap heat pack with newspaper the tape to lid of my insulated box. Then seal. I only use fedex priority over night. Just make sure if you use fedex you check weather here at night, Memphis Tennessee morning weather, then destination weather. Memphis is the main hub so if they have any weather what so ever your package will be delayed. I've been shipping 8 years and have never lost a coral because of my shipping. Mostly because I require a signature and customers forget so they miss the package. I do have a box you can have if you want to come to Broomfield