How can I remove white Dettol residue from a shower tray?

[Gramill]

We recently had a back up in the pipes so needed to disinfect the en-suite. I was pretty liberal with the Dettol disinfectant at the time. I poured it neat on to the shower tray then just sprayed a bit of water on it and then left it. Hours later I came back to it and noticed that a white residue was left. I tried washing it off but it didn’t budge !!
I have used many different cleaning product since this mistake, including… rubbing alcohol, drain un-blocker, bleach, pink stuff stain remover and caustic soda to name a few !! 😫
Any… I mean absolutely any input/help/ideas to remove the white staining will be welcomed .., thanks 🙏🏼🙏🏼😣🤦🏼‍♂️

Have you tried leaving it to soak? Plug in - water up to tray limit… seems you’re putting soap on soap? Or put a load of damp towels down.
Vingear and fairy liquid usually do quite well for reside stains too - but rinse v v well

I will give vinegar and fairy liquid a go !! 👌🏽 thanks

Is it definitely residue? Could you have maybe actually damaged the finish / coating on the tray. 😭

At this stage, I would avoid using anything stronger, especially after having used bleaches, caustic soda, and drain cleaner. You can damage the tray even more.

It would help if you thoroughly rinsed it with clean water and then attempted to use warm water and washing-up liquid with a soft cloth.

If your white stain is due to damage/etching caused by keeping the tray with neat Dettol and not because of a residue of the product, then you can't get rid of it with cleaning products. If it is made of acrylic or resin, then a polish should be considered.

I would get a sharp razor or scraper and try and scrape it up. Keep both surfaces wet and use at a 45 degree angle.