Need Help with Adjusting my existing DYI mattress

Hello,
With help from this forum i created a dyi laytex bed.
But over the last 6 months i starting having really bad back pain around my pelvis.
I’m a 170lbs male.

My current setup is as follows:
3 inch med dunlop topper
https://www.amazon.com/gp/product/B00UYG8KS4/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
3 inch med dunlop support
https://www.amazon.com/gp/product/B00UYG8T7Q/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1
10 inch med firm foam base mattress (when i originally purchased it was listed as just firm)
https://www.amazon.com/gp/product/B07BNS7RDC/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&th=1

I also really would like to better understand why its happening and what how a suggested change would help fix.
This way if it happens again i have a better understanding of what’s going on.

Any help would be greatly apprecatied.

Sorry to hear about the problem you’re experiencing with your DIY mattress. Looking over the details of the build I see a few possibilities of what the source of the trouble could be. You didn’t specify how long you have had the mattress without pain prior to the last 6 months. I suspect that the overall setup is lacking sufficient support that it initially had to maintain your spine in proper alignment.

The first thing I’d do is to have someone look at your alignment when in your primary sleeping position or take some pictures to check it. If it shows that you’re hammocking in your midsection then my suspicion is likely true. I’d then suggest checking the firmness of the base foam mattress for consistency to see if it’s possibly softened in the areas you tend to sleep in. Also check to ensure that whatever you have the mattress on is firm and not sagging under the weight of you on the mattress. You can try the entire setup on the floor temporarily to confirm that your base or foundation is providing a similar level of support.

The latex layers are less likely to have softened significantly, but the combination of 6" of medium latex may be allowing you to sink in too deeply in your midsection which can cause lower back pain. You could easily try removing one of the 3" layers (could experiment with using either one of the two) to see if that helps eliminate the problem. If it does you could get a firmer or thinner support layer and/or a thinner comfort layer to minimize your sinkage or just go with one layer on top of the foam base.

Hope I’ve given you some things to consider and experiment with to determine the cause of the discomfort you’re experiencing along with some potential solutions. Good luck in resolving the problem and getting back to sleeping pain free.

Last night I took a piece of plywood above the base foam and below the latex and had noticeable in my sleep and how my back felt in the morning.
Back no longer hurt but now it’s too firm.

Looks like i will have to ether replace the base or figure out something else that i can put between with a little give.

Thanks for the info and advice i really appreciate it.
-BB