please help with time delay circuit for pyrotechnics

I am trying to make a time delay for electronic ignition for fireworks. I will have four stations with seperate power supplies with about 200 - 300 shots per station. Due to the amount of wire to be run, I was wondering if there was a way to send one wire to the display rack and put a 2 -3 second time delay for each shot or shots. That way I dont actually have to manually trigger each shot. I can by a time delay from any of my air conditioning parts house, but for the amount I am trying to make, it would not be economical. Any sugestions would be helpful.

I am just learning about electronics, but I have a very good understanding about electricity.

https://www.electro-tech-online.com/threads/radio-design.5261/

This circuit activates the outputs one by one. You'd just have to change the values of the resistors/caps to time them how you want. Using pots, you could set up a modular system that would fire everything with correct timings in order.