We are sorry to hear you are having an issue with our filter sock rings. We did have to change our manufacturer several years ago. Our original manufacturer had changed their rings making them thinner which caused them to warp (not sit flat), so we changed manufacturers to obtain a flat ring.
We are not hearing this issue from other customers but we are aware that each sump manufacturer can make their filter sock hole size and design slightly different.
We would like to send you a 2 pack of our filter socks for free to see if they have the same issue. If this works for you, please send us your full name and shipping address.
We will keep a lookout for your shipping information.
All the best,
Lexi M
Aquatic Experts