We experimentally demonstrate dispersion tailoring of tapered fibers by immersing them in fluids. We obtain a 1200 nm wide supercontinuum in a train of two tapered fibers pumped by a low-cost diode-pumped Nd:YAG laser with a pulse width of 0.6 ns and an output power of 40 mW, where one tapered fiber is immersed in heavy water. To our knowledge, this is the widest spectrum ever generated with a system of such simplicity.