Help with Tank and Neon Tetras please!?

[Tifftastic]

Even if it looks like there's no waste in the tank the fish are producing it all the time. In the first link I provided it explains that fish exude ammonia from their gills as well as from digestive wastes.
Daily water changes in an environment where the ammonia is high will not harm the fish, it is the only thing protecting them at the moment.

 

[tanker]

Also, I would test for ammonia from the "New Water". Get a glass of new water, let it sit over night, and test it for ammonia.

 

[Finster]

I would do more than 30% until things are under control. If your tap water is dechlorinated and the right temperature I would do 50 to 70% water change.