I ordered 7. There is slight bulging at the bottom ￼when the barrels are full. So use your water quickly. And remember to put away over the winter. This photo shows the barrel is 12 full and the bulge at the bottom is about 14 of the way down from where it was when the barrel was full. Unfortunately, I have so much water to use I can’t use it quickly enough, yet. Shipment was fast and even had free natural antibiotic wipes included.