The vivi nova's are essentially oversized clearomizers. If you enjoy using clearomizers, and need more juice capacity, more durability, and want something rebuildable ( replaceable heads) you will likely enjoy a vivi nova "tank".
I greatly prefer cartotanks. I had 4 vivi novas and have given them all away to new vapors as I did not care for their flavor production. I have a theory on why this is so, but I won't get into that here.
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I'll provide some links to smaller cartotanks that would look nice on an eGo battery:
View attachment 177801
Boge F17 "skinny tank" from Vapor Beast - uses a Smoktech tank replacement carto. Looks to be made of polycarbonate so the tube could crack or melt with certain flavors. $ 8.00
http://www.vaporbeast.com/product_p/c47.htm?Click=391
SCT-v2 tank from Vapor Phoenis - uses a typical Smoktech tank replacement cartomizer, 3.5 ml capacity. Polypropylene tube safe for all flavors of juice without cracking. Available in a frost clear and frosted colors. $6.00
510 SCT-V2 3.5ml Tank
Replacement 2.6-2.8 ohm single coil cartos with laser-slotted hole for any 45mm length cartotank. $2.00 each (cheaper if you buy 10 or more).
Replacement Cartomizers 2.6-2.8ohm 510 SCT-V2
Polypropylene DCT Tank kit from My Vapor Store - Choose the slimmer 3.5 ml capacity, juice-safe polypropylene tube in frosted clear or frosted colors, with drip tip and 5- pack selection of single/dual coil cartomizers, ohm rating, number of laser-drilled holes. $21.35.
510 Pro DCTank Combo
IBTanked pyrex tank kit - 2 ml capacity pyrex glass tank with stainless steel endcaps, combination drip tip/tank filling tool, the correct cartomizer needed for this tank, and a "thingy". $ 25.00. Additional cartomizers and drip tips available on the website.
https://www.ibtanked.com/kits/complete-tanks/19mm-clear-tank-detail
View attachment 177799View attachment 177800 IBTanks on eGo's.
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The below
Safe Vaping Power Chart will show that a
2.5-3.0 ohm cartomizer will provide the widest range of voltages for a variable voltage eGo Twist or Spinner.
Vaping Power Chart 2.0 - Imgur
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My
blog entries have detailed descriptions of how to fill your cartomizer and tanks, including a demo video. Click on the link below my avatar.