All Safety Liners have a tendency to move or creep down the side of the frame and in some cases pull the side of the foam frame down. This is caused by sitting plum on the edge of the frame. Its best practice to avoid this by sitting over the edge of the frame when getting in to bed and swinging your legs over. Same when getting out. Sit near the edge with your feet on the floor and push up with your hands.
Safety Liners are there to catch water in the rare circumstance that your waterbed should ever develop a leak. Check it occasionally to ensure it is as it should be. Gently Push the bladder away from the foam frame where you hop in and out and if there are any creases in the liner, Pull it back up. It is better to have a chair to sit on.
The Original safety liners have around a 5 year lifespan if Maintained. Bag liners were invented with the intention of preventing liner creep as they encase the whole foam frame like a pillowslip. In practice this has not always worked out as intended. When servicing and relocating waterbeds, I have seen many busted bag liners. And have seen many foam frames that look to have collapsed on the edge due to a bag liner pulling the side down due to trapped creases.
Waterbed Liners 2.0 Made from Mattress material with 30cm wide straps running Full length and width underneath the frame. The best yet with an expected 20+ year lifespan. Available on all of my King and Queen size Waterbeds.
Standard Liner's have around a 5 year lifespan. This one with Zero Maintenance Over a long period of time. Notice the foot is still perfect.
Bag Liner that has split due to too much Tension on it. Around 2 years old
Bag Liner that has pulled the foam frame down. Around 5 years old. The call out was to replace the frame.
Heavy Duty Liner made from Mattress Material. The Best Available. With a 20+ Year Lifespan
I Love My Waterbed, Its The Best, I Make Sure Yours is Too!