there are no nitrate eating bacteria. water changes only answer to nitrate creep, make sure you vacuum well, feed appropriately, maintenance your filters and do your water changes. all my tanks get a fin level water change and vacuum every week except the 180, its twice a week. water changes are the only way to keep your nitrates low. you can have less fish and do less water changes, or more fish and more water changes. but either way the water changes need to be done.