Should I remove second hand 3d background if it can't be cleaned properly?

[Tiber]

I bought a used tank today. Its in good condition, but needs a clean as I think it has laid empty but a bit of water in the bottom for a few months.

This is all fine by me. My one concern is the 3d background, it seems to be made of a foamy material and still feels wet to the touch.

It looks good, but I'm wondering if I should just rip it out? I have no idea how I can properly clean foam? Maybe I'm just overthinking it but I've now got it in my head that the background could let nasty bacteria or something into my water.

I do like the way it looks and as its glued (or siliconed?) to the glass that presents issues of its own, so I suppose I'd rather not remove this on a whim if I'm just overthinking it

 

[mbsqw1d]

If anything that 3d foam background will be a great place for harbouring beneficial nitrifying bacteria. But if you're worried about what it currently holds, with it being 2nd hand and all, then I'd either fill that tank and heavily dose with salt and leave to sit for 24 hours. Or dose with pure bleach (as in just bleach, no other cleaning chemicals or fragrances). Then rinse thoroughly and use a dechlorinator (Prime) at triple or quadruple dose. If you like the look of it, I'd keep it.