Solid Hardwood, Engineered and Laminate Flooring - Dog urine soaked hardwood floors

I just removed carpet in an old rental and found serious urine stains (smell and blackish rings) on the hardwood floor. I ran my sander over it with 36g – 80g. I then tried bleach 50% strength, than a second time with 100% and a scrub brush. Re-sanded and the stain is still there. I only have 3/8“ surface to work with. If I can’t remove the stains, is it possible to hide with a dark floor stain? The new owner wanted a red oak stain color, but it shows the urine stain big time.:wall:

Once you're down to raw wood, bleach will remove the stain, but it might take multiple applications and you may have to bleach the whole floor to get even color.

The bleach will not ride the black, then after board replacement, anywhere the bleach touched the existing wood, there will be a halo.

It sounds to me like Mocha, Java, stain or black laquer, is in the floors future, or a complete replacement.

Thanks guys. I'll mix a batch of dark walnut with red oak to see if I can create dark with a red tint. The little lady wants a red tint. Suggestions welcomed.
This urine stuff is throughout 5 rooms in the house so it is too much to replace. And yes, there were halos from my bleach processes which cause me to come to you guys for help. Thanks again.:thumbup: