This study examined the effects of chemical blends (a combination of alum and aluminum chloride) on pH, N, and pathogens in duck litter during a six-week experiment. In total, 240 Pekin ducks (160 males and 80 females) were individually distributed into 16 pens, in a randomized experimental design consisting of four treatments and four replicate pens per treatment. Our treatments included a control, T1 (75 g alum + 75 g aluminum chloride/kg duck litter), T2 (100 g alum + 100 g aluminum chloride/kg duck litter), and T3 (150 g alum + 150 g aluminum chloride/kg duck litter). There was no difference among treatments in pH and Total N (TN) at weeks 2, 4, and 6 and weeks 1, 4, 5, and 6, respectively. However, there were significant differences in both pH and TN among treatments at weeks 1, 3, and 5 and weeks 2 and 3, respectively. Regarding pathogens, we found small differences in all treatments in Escherichia coli populations from weeks 1 to 5 and in Salmonella enterica populations from weeks 1 to 3. In conclusion, the addition of chemical blends to duck litter increased TN, which resulted in a lower litter pH, but did not significantly affect pathogen populations.