There is nothing you can do, except remove/lessen the problem. With this being a brand new tank it is even more likely to be ammonia poisoning.
Take a sample of your tank water to a pet store, most will test your water for free.
Daily water changes are required to keep ammonia and nitrite levels as low as possible during a cycle. There are water conditioners out there that will detoxify ammonia and nitrite, but they only work temporarily (a day or two) and are meant more for people who have ammonia and/or nitrite coming right out of the tap water.
Fish produce ammonia as waste, bacteria will colonate the tank that converts ammonia to nitrite which is even more toxic to fish. A different bacteria will convert that nitrite into nitrate which is the least toxic of the three. Nothing will remove nitrate except live plants, or partial water changes (however partial water changes are still required even with live plants).
This process is called a 'cycle' since if you test daily you will see a spike of ammonia, then a spike of nitrite while ammonia goes down to 0, then nitrates will rise while nitrite goes down to 0.
This cycle takes a minimum of 2 weeks if you seed from an established aquarium, to up to 8 weeks to complete, 4-5 weeks is an average.
Here is a sticky post that explains all about it, and methods that could have been used prior to owning fish. http://www.tropicalfishkeeping.com/f...m-cycle-38617/