I recommend either of two
tanks below for a first
tank. Both are a high quality tank yet inexpensive should you find out that using a cartotank is not for you.
My Vapor Store has a polypropylene-tubed tank kit for about $23. You get the tank, metal endcaps, a drip tip, and your choice of five single/dual coil cartomizers, resistance, and number of laser-drilled holes. Available in a 3.5ml (slimmer) and 6 ml (wider) capacity size for the same price. The polypropylene tube is safe to use with cinnamon and citrus flavors which can crack or melt polycarbonate-tubed tanks, and available in a frosted clear or a few colors.
510 Pro DCTank Combo
IBTanked offers several sizes and other options for a pyrex tank and either stainless steel or anodized aluminum (22mm only) end caps. Available to purchase separately (tank and caps) or as a tank kit (tank, caps, cartomizer, combination drip tip and tank tool) for between $24 and $30 depending upon the size of the tank you choose. You can also "bling" out your tank with custom painted tank tubes or colored anodized aluminum caps for a few more bucks. I presently have 12 of these tanks (obviously a favorite of mine).
https://www.ibtanked.com/



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I've written several articles in my blog
E-Cigarette Forum - Baditude - Blogs which cover a cartotank tutorial, juices that can destroy a plastic tank, a review of the IBTanked, and a list of online vendors that sell pre-punched cartomizers.