Question: Physical Sciences It is important to maintain a low ammonia-ion concentration in freshwater aquariums to ensure healthy fish (and plants). An ammonia neutralizer is advertised to almost instantly detoxify ammonia (i.e., reduce the concentration of ammonia ions) in order to protect fish. Fourteen untreated 20-gallon aquariums were selected at random, and the ammonia-ion concentration (in ppm) in each was measured. One hour after the directed amount of the neutralizer was used, the ammonia ion concentration was measured again. Assuming normality, is there any evidence to suggest that the neutralizer decreases the mean ammonia-ion concentration? Use a = 0.025.