Hi TanJent,
I’m glad that you were able to figure this out and I hope that the new design works better for you. I’m looking forward to your next update.
Outside of your sheets and bedding there are generally 3 types of products that are used on top of your mattress but the differences between them can have “fuzzy edges” and the terminology for each of them is sometimes used interchangeably.
The first is a mattress protector. A mattress protector is designed to protect a mattress from the body oils and moisture and skin cells that we release each night and to protect against spills and accidents as well. It also protects the mattress warranty because even a small stain or a watermark that is the result of removing a stain can void a warranty . They are easily removed for cleaning and are an important part of keeping your sleeping surface in a clean and hygienic condition. They are designed to have the least possible effect on the “feel” of your mattress and are generally thinner and often more stretchy. Post #89 here has more information about the different types of mattress protectors which all have different tradeoffs between the degree of water resistance that they have, the amount of airflow they allow and their effect on sleeping temperature, and on the effect they have on the “feel” of your mattress.
Mattress pads on the other hand are thicker than mattress protectors and generally have some additional padding that is designed to change the feel of your mattress by adding some additional surface softness but can also reduce the ability of softer foam layers below them to compress and contour to the shape of the body so even though they may add some additional surface softness if they are on top of softer more contouring layers they can also create a firmer feeling as well. Some of them are also water resistant or waterproof so they can double up as both a mattress pad and as a mattress protector. Some thinner mattress pads will be similar to some thicker mattress protectors so there may be some overlap in thickness and in terminology. There is more about mattress pads in post #10 here.
Finally there are mattress toppers which are thicker yet and are designed to have a more significant effect on the pressure relief and feel of your mattress. They aren’t designed to protect a mattress … only to change how it feels and performs and to add additional softness and pressure relief. Some thinner toppers will be similar to some thicker mattress pads so again you can see some overlap in thickness and terminology.
If you have a mattress that is a good “match” for you in terms of PPP and your mattress doesn’t need any fine tuning either with a mattress pad or a topper then a mattress protector that has the least possible effect on the feel and performance of the mattress is generally the best choice.
Phoenix