This should be helpful, although a bit long. Get comfortable for a few minutes.
I've used, and love the Aspire BDC, as well as the nautilus. I have new & shiny syndrome pretty bad, so I bought the nautilus before the stainless steel tank came out. I dropped the glass tank on my tile floor in the kitchen, and of course it broke. I gave up and went rebuildable and bought an Aqua dual coil rebuildable tank, as well as a patriot clone RDA. You don't care about that, so lets get to relevant info. Although I mention all that for a purpose that won't initially be evident.
Cleaning: Sambuca has it exactly correct. You must do this. Either use polident to clean, or rinse in extremely hot water at the end of the day. I've tried a vodka soak, didn't work. I tried dry burning, didn't work. Sambuca's method works because you need a non toxic compound to eat away at the crud, which makes it easier for it to be cleaned when rinsing in hot water.
If you don't want to fiddle with building your own coils, the trade off is that you must clean them frequently. Or make more money to keep buying heads. Again, I recommend sambuca's method.
Why dry burning does not work:
No matter how you do it, it's going to end up sucking very badly. You have dual coils which are criss crossed over each other. By the time your coil is gunked up from either a few days or a few weeks of use. *depends on your juice* what dry burning will do is melt the carmelized juice off the coil which is hot as hell, and all that crap in it's melted lava state will soak into your wick. Then thinking it should work, because you can see the coil glow *facepalm, you fill your tank with juice and it tastes like crap.
With these aspire tanks you have to take care of the coils by cleaning them. I know people say dry burning is fine because the silica won't burn, which is true. But the problem is exactly what I mentioned. The wick will soak up all that burnt and carmelized juice.
Other problems:
Your coil is brand new, and it's leaking, flooding, gurgling.!!! Aargh. What to do?? The problem is 99% associated with air flow. Pbusardo does a long version on his youtube channel. Basically when you take a pull, it creates an air vaccum inside the tank. This is how the juice is pulled to the wick then vaporized by the coil.
The only long term solution is to have the air flow controller ring *aspire bdc vivi's. (the nautilus has it built in) Normally people having the leaking gurgling issue are using a device where they flush mount the tank onto the device. The bdc vivi's are getting air flow directly under the 510 connection pin. Because of this, those experiencing leaking are pulling at a rate too fast for the tank to effectively vape.
Vaping is similar to a car. It takes heat *fire, juice *gas, and air for it to be effective. If there's too much of one component = functionality problems. The air flow control ring, enables the tank to be lifted off the direct 510 connection exposing it to more air. Now the coil gets enough air to vape effectively based on the strength of your pull.
Hopefully some of this rant was helpful. My examples should help you troubleshoot no matter what device, tank you're using. The problem is going to normally be either too much, or not enough of Heat, Juice, or Air.
No matter how frustrated you get, at least it's not a stinky. It will get better. You will find what works for you.
Stay calm, vape on.
PS. If you do get into rebuilding, rilp trippers is the man. An excitable fellow with an array of innovative coil builds. It gets easier. If a 70 year old lady named Jeanie who smoked for 53 years can rebuild her coils, I think you might have a shot at being successful.
