The power went out but your family continued to use water. The Well-X-Trol tank has several gallons of water stored within the air pressurized bladder and is generally enough for a few toilet flushes or turning on other fixtures. As the water emptied out of the bladder tank, a great amount of iron sludge came off of the inside of the bladder and entered the aggregate filter. While this filter is designed to remove this precipitated iron, the huge amount of sludgy iron clogged the filter and all it needed was a few extra backwashes, which I took care of while I was at your home. The pressure improved after the manual backwashes.
The best approach is to stop using water when the power goes off so to prevent this fouling of the filtration system.
Water problems in Connecticut? Call Ted Mullen, of Clean Water Man, Inc. at 203-417-9601.