I'm trying to create a sous vide box using a cooler and water heater element. My question is since I'll only be using 120v should I use this 8" 1500w 120v element
http://www.amazon.com/gp/product/B000KKVZUO/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=ATVPDKIKX0DER
or this 14" ripple 5500w...