I might be able to help with that Aspire Nautilus
The only time I seen a Aspire Nautilus leak was from over or under tightening the coil.
I know I know everyone thinks they don't over tighten but
please read this.
The coil is what normally leaks and that should be finger snug not tight. There is a little o-ring on the bottom of the coil right above the threads and if you over tighten, that o-ring gets smashed and will leak. You can see it in the picture below.
In that picture the coil to the right you can see it standing up, there is a hole at the bottom, then threads then that O-ring that I am talking about, it is under a little flange.
When I open mine up to refill my tank my coil becomes real loose to where it will leak. and I have to snug it up again. That is how loose I keep my coil.
The trick is to make it tight enough to stop it from leaking but without crushing that o-ring.
If I do over tighten it and crush that o-ring you can use a little eyeglasses screwdriver and slide it between the o-ring and that little flange to try to puff it back up again. but if it is too flat it might always leak.
First thing is to make sure the airflow is free of any juice, once there is juice in there it's hard to tell if it's still leaking.
Take the whole tank apart, even take the coil out. With a paper towel to catch any juice, blow thru the side adjustable air hole. and any juice in there will come out where the coil was.
Now when you go to put your coil in, just screw it down till that o-ring touches, and then not even maybe a quarter turn.
Here is where the tricky part starts with the Nautilus.
See the top of the tank screws into the top of that coil, so when you tighten down the tank the coil could spin a little and tighten up more.

So if it is tight to begin with, it can be over tightened when screwing the tank back on.
So even if you don't over tighten your coil, if you over tighten you tank it will spin the coil and over tighten the coil
And another problem is that when you take your tank off to fill it, the same thing in reverse can happen and it can loosen the coil without a person knowing and when they put it back together it will leak. So any time you take your tank off make sure that coil is still snug.
The tank is the easy part, it don't have to be tighten down that much either. Just finger snug. Soon as the glass touches the big white gasket, the same thing, maybe just a quarter turn. If it's going to leak there it will do it right off the bat. And this is where you would rather have it leak from because you just snug it up a little bit tighter and it will stop.
The Nautilus is a good tank, but learning how snug to make the coil can be a little tricky.

It's in our nature if something is leaking, make it tighter lol. This is not the case in vaping.
I hope this helps