All Clover device printers except for the Kitchen Printer are thermal printers, so they do not need ink cartridges. If your Clover device is printing receipts without ink, please make sure you are putting the paper rolls in the printer correctly. You can also reach out to your Clover rep to make sure the device isn't malfunctioning.
The Clover Kitchen Printer does require ink ribbons. You can order ribbons from the Order Paper app through the below link.