Water/Rust stain

[KEVIN_374348023]

Just checked on the caravan in it's winter storage, and there's a rusty water stain where water has dripped through the barn roof.

any ideas onb the best product to clean this

 

[Rogerdraper]

Try citric acid crystals from a home brew shop .Add a few drops of water to the crystals to make a damp paste type compound and the rub on . Citric acid is only lemon juice but in a crystal form and is not very strong .BUT use with care .I would be glad to know how you get on . i have heard that folk have used this idea on baths where a tap has been dripping.good luck take care with it.