Hi AtTheBeach,
Welcome to the Mattress Forum! 
Thank you for your comments about your Naturepedic mattress. Iām glad you are enjoying it and it is working well for you.
If you are using a true active coil box spring, I would recommend that you replace it with a foundation that would be of a high enough quality to support your mattress. Naturepedic states that you should use a solid platform or foundation that is equivalent to what they offer, or their warranty will not cover the item. The foundation thread here speaks a bit more about appropriate options.
Phoenix