Just bring your empty cartridges to us and we will, depending on which cartridges you have and what condition they are in, refill or swap them as quickly as we can! (We also have new cartridges for many HP and Canon printers, should you need them.)
In almost all cases, it is desirable to refill cartridges soon after they are emptied. This helps to keep the residual old ink from drying out or deteriorating inside the cartridge, which can degrade or ruin a good cartridge. To minimize drying, we suggest storing and transporting depleted cartridges in an air-tight, hard-plastic container, like an old Tupperware or Ziploc container, or even an old yogurt or butter container. We do not recommend storing or transporting printhead type cartridges in plastic bags as the bag can wrap around the printhead, causing residual ink to draw out by capillary attraction, making a mess and, possibly, ruining a color cartridge by cross-contamination.