The beauty of the Kangertech tanks is you dont need to know anything to use one.
You can keep buying coils and replacing them.
But when you start to wind your own coils thats when the tuning starts. This tuning holds true for allmost any tank. Be it a Kayfun a kanger an ithika etc.
You have your variables.
a. Coil as in what size, what ohms, what style of wind, how many, ribbon or round etc. This Ive explained you want it to glow red hot as soon as you touch the button.
b. Your juice. As in thick, thin,
c. Your air flow.
How is the air flow limited. Is it fixed, can it be changed, can you drill out the holes, is it via the 510 connector etc.
d. Your bat and power. Here again you want the bat you have to get the coil to glow as fast as possible.
e. How you draw slow or fast. Hard or soft.
Most common problems you will run into when building and tuning.
1. Not enough smoke.
This can be blamed on your juice quality and composition. Too much PG and too little VG gives you bad smoke.
juice is too thick so flow is slow and the wick is not as wet as it should be.
Bat and coil combo just are not getting hot enough.
Not enoughf wick exposed to juice.
Coil wound too tight choking wick.
Not pulling hard enoughf. To form a vaccum and get the wick juiced.
The tune is you have to balance air flow into the tank. i.e. too easy a draw and you loose out the formation of a vaccum which pulls juice into the well / wick. If the draw is too tight because the air flow holes are too small then You have too much suction in the wick area and it gets flooded which can again result in less smoke and gurgling.
To solve this tuning problem you need to understand where your juice is. Whats keeping it there. How its going to enter the wick and reach the coil.
I still love my Kanger Mini Tanks. The 2 has a super tight draw. So I put the latest adjustable air flow valve on it. Now its super easy draw but now due to the drop in suction juice is not flowing into the well or getting the wick wet.
So I have to re-build the wick This time I pack the wicks into the head very loose. This allows juice to automatically flow into the well. At the same time not so loose that it floods. You have to balance the fact that you dont want your juice flooding. But at the same time it must flow with the reduced vacuum that no longer exists cause you have made the air hole large.
The Pro Tank 3 right off the bat has a very airy draw.
Gurgling.
Gurgling is caused when too much juice enters the well or the wick and coil area. This can happen if the juice it too thin.
It can happen if the draw is too tight and air flow is poor due to too small a hole or a hole getting blocked with dirt. So now when you draw the increased suction is causing the juice to get sucked into the well.
You can cure this by
Making your juice thicker
Re-packing the wick area arround the head. Pack it more dense So juice flow is harder.
Your getting the picture.
For me a well setup tank is one where you have a very easy airy draw. And you have thick white clouds of smoke. With no gurgling. Some of the boys have experienced this when I did my first build on the Ithika. Air flow fully open. Juice flow fully open.