Hello fellow nurses

One of the problems with my plants

seems to be Salt build up.

I rarely use MG for Tomatoes, but have used it half strength.

The plants are in containers and drain well,

I guess the salt could be from the MG, but I water

more often with plain water and see water readily drain

through. If it is my city water causing the salt, what can I do to improve it? Should I use water from the hot tap?

Will letting the water stand,reduce the amount of salt.

Is their a product to add to water that will desalinate?

Use distilled bottle water? Stand on 1 foot and spin around three times?

Any and all help will be most appreciated!

Rick