Hi HarborRV,
You cannot use a discount, because the calculation can only be done after the customer has put the desired quantity in the basket.
What you can do is to create several prices for the same product, the price that is applied is based on the quantity established for each.
The main difference between this option and discounts, as they are in hikashop (and other platforms), is that 2 prices will not be displayed in the front end "new price" - "old price", but the price will change in the basket when the condition based on quantity is confirmed.
To use the percentage, as you wish, you can create 5 coupons, with the option to be automatically loaded into the basket when the required conditions are met.
The condition being again, the quantity.
But in this situation, you are limited to one coupon per shopping cart.
If the customer puts 2 different products in the cart, with different quantities, only one of the 5 coupons created by you will be applied to a single product in the cart.
To be able to use this option with several coupons at the same time, you will need to use this plugin
https://www.hikashop.com/marketplace/product/164-multi-coupon-checkout.html
But wait a little longer, someone from the staff will surely answer you.