I've had my new Equalizer mattress from Jamison for three nights (which I know is a short time). It is composed of a 3" Talalay Latex (24 ILD) top over a 7" foam core. I bought the box that came with the mattress. I previously had a 10-year old Sealy Posturpedic innerspring mattress that was too hard for me as a side-sleeper.

My new mattress seems comfortable at first but I seem to sink too much, and I am waking up with lower back pain which I did not have before. I sleep on my side with a pillow between my legs. I am 5'6" and about 195 lbs.

I am not sure if the Talalay Latex is too soft, or if the problem is that I am sinking through to the foam core which is too hard.

At this point, I want to know what my options might be. Would some kind of mattress topper make it better, or worse? Or, should I just give it some time? Anyone have any suggestions?

First of all, if you think that the problem is that the mattress is too soft, there's not much you can do in the way of a topper, etc to make it firmer. That is why it's ususally better to start on the firm side, as it can be made softer with a topper of latex, foam or memory foam.  There are people that just can't sleep on a foam type bed, not sure if you are one of them from what you've described. 

You say that it is 3" of latex over 7" of foam. Is there also a pillowtop on the mattress over all of this? If so, the pillowtops are usually a few inches thick and are made of cheaper PU foam, they will feel very comfortable in the store.... but upon sleeping on them will often times end up being way too soft.   They also form a 'rut' or 'canoe' in time as the foam breaks down.  Almost without fail. They are to be avoided.

What to do?  Did the store give you a satisfaction or exchange policy? If they did, then see if they have something firmer and without a lot of pillowtop.  You can then soften up the top layer to your liking through various toppers.  If they don't have a 'satisfaction' policy, you might be stuck with it.  I'm sure some other people on here will give you some other suggestions also. Good luck.

Bill

Thanks for your response Bill. The info about the topper is helpful, at least to know it won't help! :-)

I did do some research before buying, and it is NOT pillowtop. And I did lie for a while on the mattress I bought, in two different stores. The back problems only seem to have emerged after sleeping all night on this mattress...

There is no option for return, which I found at all the places I looked. But, I not really sure what the reason for the problem is... Anyone else have any suggestions?

What you describe sounds like the 7" of foam is too soft to support you.  That is why the back ache shows up only if you lie on it for a long time.  For short periods of time, your back muscles will support you.  After a while they begin to ache if they have to work for hours.