How can I get water, rust, & gunk of toilet water knob?

You could try a toothbrush and scrub but it looks pretty rusty to me. You can go and buy a new round "thingy"! The ones I have seen are hinged so you just open them up, pop them on, and close them. They are NOT expensive. You can also buy a new flexible hose that goes from the toilet to the wall. I would bet it would cost about 10.00 to make it look a whole lot better!

spray with Iron Out let sit for a bit then scrub off. Find at home depot or Lowe’s. Effectually May need to replace.

I agree with GK, defiantly replace the water hose line.

Dont think any of that will ever look good. I would buy new. Turn the water off get a pipe wrench remove old and add new. If not sure about size take old items to the store with you. Dont forget teflon tape. Hope that helps

I would use some naval jelly on the rust with a fine brass wire brush and steel wool. Be sure to wear rubber gloves as its caustic. Once the rust is off, coat is with a quick spray of WD40. You can get all this at the hardware store. You could also get Rustoleum Rust Dissolver.

Thank you! I will try this!

The copper pipe coming out of the wall is corroded. It can be cleaned with some emery cloth or fine grit sandpaper. The wall thingy

( escutcheon plate) is rusted on. To remove the plate you would need to turn off your water main, flush the toilet, remove the toilet hose ( I suggest replacing it), and remove the shut off valve. Then you can pry off the escutcheon, replace it with a new one, reinstall the shut off valve, and install the new toilet hose. Turn your water main back on and make sure the shut off valve is open. Check for leaks.

If you don't want to go through all that you can clean the plate with a stiff brush and sandpaper. Slip some paper or tape behind it and paint it. Clean the copper with a strip of fine grit sandpaper. Replace the toilet hose. Take the hose with you so you get the right length.

I would try a product called C-L-R (comes in a small hard plastic rectangular bottle). Get and old cloth and pour a good amount onto it and then wrap it around the rusty thing. Let it soak well for 20-30 minutes then wipe away and see if that has helped the problem. Repeat and scrub until the crustiness is gone.

If you can, call in a plumber to fit new for you, if not possible. rub with Wire wool or spray WD-40 and wait a while and then rub off. Fill the gap with silicone filler and then use Metal Primer/undercoat and then paint all that is discoloured to look good again.

You can buy a new escutcheon [the round thing at Lowes, Home Depot even Amazon. They are not expensive. Get the one that comes with a slit so you can just wrap it around the pipe. I would spary the escutcheon with a clear coat. The pipe looks like it is rubberized, you may have to replace that also, but I would try to clean with peroxide or CLR with a magic eraser.

Hello, try some vinegar to loosen the hard water grip on things, then use steel wool to clean them up