If you use the ‘right chemistry’, you will see the desired results almost immediately.
Of course preexisting conditions like other chemicals that may have already been applied may influence the result.
Looking at the right portion of the stained area about 6 inches in from the right is an area that looks like something was the ‘right chemistry.’ Do you know that something ?
The overall look is that of wicking – carrying of soils/ oils/organics/metallic ions to the dry line.
Try cleaning with Soils and Oils.
Try oxidizing the organics, with White Knight.
Try a rust remover for the metallics. Oxalic or stronger.
A couple guys suggested a stronger acid. Vinegar is a poor choice; considered weak and very odorous. A stronger acid which is odorless would be hydroxyacetic (glycolic) found in many all fiber rinses. You will see acids work miracles on natural fibers. Did you try it? I used to carry a small bottle of 60% glycolic just for this situation. If the ‘right chemistry’ is an acid, this will work immediately.
A couple guys suggested Sally’s which is 12% peroxide. Did you try that? Even 3% H2O2, applied fresh, directly to the stain will show you immediate results – if that’s the ‘right chemistry’.
If your peroxide is flat, you got water.
One really smart guy suggested Distilled water which will pull the hard water ions out – the ‘right chemistry’ really might be as simple as that.
