How high is high? You aren't giving us much to go on here. What type of substrate to do you have? What type of filtration are you using - power filter, cannister, wet/dry? Are you using a skimmer?
There are several ways to export nitrates from your tank...
1. Water changes - once a week for several weeks. Cleaning any foam filters from cannister once a week. But unless you figure out what you're doing to elevate the nitrates, the same problem will happen over and over.
2. Grow nitrate consuming plants like good algaes - Caulerpa
3. Convert cc bed to a 4-5" sand bed and get 1 - 1.5 lbs of live rock per gallon of water. Crushed coral traps detrius which converts to nitrates.
4. Get a skimmer - this will remove proteins from the water before they can turn to nitrates.