NOTE: These BVC Replacement Coils are compatible only with the Aspire Nautilus, Nautilus Mini and Triton Mini Tank models. They won't fit Aspire K1. There are specially made Aspire K1 replacement coils for this tank.
Replacing the Aspire Nautilus and Nautilus Mini coils: Remove the bottom cap, unscrew the old coil and install a new one. Add E-Liquid if it's low and return the bottom cap. Depending on the frequency of use, expect for the coil to last about 2 weeks (less if you're a heavy vaper).