How to clean jets in bath tub and get rid of ugly hard water steaks

vinegar a cup or to 2 it's an acid and lime is a base. add it after the water is at a full level.

Start by filling the tub to cover the Jets. Pour 1. gallon of vinegar in the tub, and turn the jets on. The water in the tub recycles through the jets, let it go for, 20 minutes, and scrub the holes as the water comes out. Drain and rinse with a sponge to clear any ring in the tub. Good Luck!

https://www.maidbrigade.com/house-cleaning-tips/how-to-remove-hard-water-stains/

Jets can be cleaned easily with straight vinegar. A product called heavy duty scouring stick by Pumie is great for anything with hard water stains. Available on Amazon. Don't use this on plastic though. Only porcelain.