The T3 and T3S are my favorite all day use tank systems. I'll answer xt's comment on the Kanger heads, the T3S head will work in any Kanger tank, T3 (with proper base)/Evod/Protank/Protank 2/Mini T3 (with proper base)/MT3 (with proper base)/MT3S, however, a protank or Evod head will not work in T3/T3S/MT3/MT3S/T3 Mini/MT3 Mini, the chamber of the T3 form factor we'll call it is like half to quarter milli-meter narrower than the other systems on the heads.
Anwer to the OP's question has really been answered, but I'll emphasize more, based upon my experience.
General maintenance on the T3 and other Kanger BCC systems is pretty simple, and basic.
Lighter, thinner, and less sweeter liquids tend to require less maintenance as they don't clog and choke up the coil and wick as quickly as darker, sweeter, and thicker liquids do. Best options are to have coils and tanks in a rotation schedule, meaning several unsealed, yet cleaned and awaiting use, several in use and service. Thinner, lighter, less sweeter liquids I clean out the tanks every 3rd to 4th refill, darker, thicker, sweeter liquids every refill or 2nd refill. Heads on coil clogger liquids I rinse every 2nd refill under warm tap water, dry burn, then rinse again and let sit out to dry, put my spare heads and tanks into use and service, thinner liquids I do this head maintenance every 2nd to 3rd refill. Every dry burn cycle I'll generally soak the heads in everclear for about 20 minutes before the dry burn to loosen up gunk in the wick choked at the coil. Having heads and tanks in use and others sitting drying and cleaned helps extend the usage and life of your heads before needing replacing or rebuilding. T3S/Evod/Protank heads are far more easier to rebuild than older T3 heads are I might add, don't have to fiddle getting insulators, center post, and trim wires inside an Ego cup.