I am able to raise and lower the water level in the toilet tank but doing so does not seem to effect the level in the bowl. I have a kohler one-piece toilet, 1.6 gallons, about 5 years old. Thanks!

The level of water in the bowl is not adjustable, its set by the design of the trap inside the toilet. If you add any extra water to the toilet that same amount of water will flow out of the trap. What issue or problem are you trying to correct?