what should the researcher add to the aquarium to decrease the concentration of ammonia in the aquarium?

Codominance is when alleles have the same amount of dominance and both are expressed in a heterozygous individual(ab blood type, roan cow). in a heterozygote with incomplete dominance, the phenotype seen is an intermediate of the dominant and recessive phenotype.(pink flowers when the dominant form is red snd recessive form is white)

To kill bacteria from our body especially from stomach