I don't know what to tell you as you are talking of two completely different setups.
A dual coil tank uses a cartomizer; most likely you used dual coil cartomizers in that tan. Dual coil cartos require a lot of power to work well. What setup do you have? If you have 3.7 V device then there can be no comparison between a LR carto and a dual coil. What you can do is try an single coil XL sized cartomizer (for instance the Resurrector from Crystal Clear vaping) in the DC tank. That should vape exactly like a LR carto would, only better as it'll stay wet all the time. You will also want to punch or slot your own cartos because the pre-punched holes are always too small, especially for thick juices. Also, you must first fill the carto as you normally would before putting it in the tank and vaping it otherwise you run the risk of burning the filler.
On the other hand the Vivi Nova is a wicked "clearomizer"-style tank. I had a fairly bad experience with the unit I tried - they may have fixed it since, but it had a terribly muted and distorted flavor and an added burned rubber taste that actually came from a rubber grommet that comes into contact with the resistance wire. Go figure. Again, I wouldn't know how they work if they are now fixed, but I also know that people have found ways to mod them and make them vape better. You can either look into that or, if you are set on clearomizers, try other models that are said to work better. Noteworthy is the the so-called Pheonix bottom coil clearomizer that seems to do a great job. Some people also found that the "Stardust" CE4+ clearos work decently well with thick juices.
Again, the tank specifically should not change flavor (unless it leaches plastic into the juice which can happen with acidic, cinnamon and citrusy liquids in polycarbonate tanks).