How to pay for supplies with coins not gems

[fastcatiecat]

I have these crates over my businesses and it says I need supplies but only option to pay for them is with gems. At the top of my screen the crate icon is empty. Please help.

[kooky panda]

When you run items in your industry buildings(greenhouse, industrial plant, or idea factory) you will produce goods(little crates).

When you collect coins from your business buildings, you then need to supply the business building with more goods.
When your crate icon is empty it means you are out of goods, so you will need to run more from you industries buildings.

[kahlan531]

I have these crates over my businesses and it says I need supplies but only option to pay for them is with gems. At the top of my screen the crate icon is empty. Please help.

The only way to obtain goods is to make them with your industry buildings, as kooky said, or to purchase them with gems. There is no option to purchase them with coins...and I'm sure there never will be as this is TL's business model.