I am a dedicated user of Nano Clearos, both 808 and 510. At $2.00 a piece, you can't beat the price, better than whistling in the dark with cartos. Some advice:
If it gets gurgly, take it off the battery, and blow it out from the battery end. When refilling, put the tip between the same fingers that are holding the clearo, and don't waste a second. With a virgin, let it sit for an hour before using. If you follow that simple advice, you will find that Nanos are easier to use than CE's
Do not wash them. Dedicate one to each flavor. If you really want to re-purpose one, like when boosting a
juice to favored status, dump what is left, give it one quick rinse in water, then refill with unflavored. Vape until all you can taste is the vg. Then refill so that the antibacterial action of the pg will protect it from going bad.
Never use a dark juice in a Nano. It WILL die quickly. Use something else, or toss it if it does not go to favored status immediately.