Waterbed sheets and other bedding are specially fitted to accommodate the flexible shape of a waterbed. While a soft side waterbed can use conventional bed sheets, hard side waterbeds require sheets with deeper corner pockets. Bedding with an attached top sheet ensures sheets stay in place. Like traditional bedding, waterbed sheets are available in a large variety of patterns, materials (cotton, polyester, silk and more) and thread counts. Look for thread counts of 180 and higher since these sheets tend to be of better quality and last longer.
Waterbed comforters and waterbed blankets are generally smaller than their conventional counterparts. Waterbed comforters and waterbed blankets tend to be tucked between the frame and mattress (of hard side waterbeds). However, that is not to say you can't use traditional comforters or blankets. They would just have to drape over the side of the bed.
Another important piece of bedding is the waterbed mattress pad or cover. In addition to allowing the skin to breathe (maximizing sleep comfort), waterbed mattress pads prevent body oils from damaging the vinyl. The mattress pad also preserves heat and helps protect the mattress.