Final answer:
Ammonium from fish waste can be converted into less toxic forms such as urea or uric acid. In the liver, ammonia is converted into urea, which is excreted by mammals including humans. Reptiles and many terrestrial invertebrates, on the other hand, excrete ammonia as uric acid.
Step-by-step explanation:
Ammonium from fish waste can be converted into less toxic forms such as urea or uric acid. In the liver, ammonia is converted into urea, which is excreted by mammals including humans. Reptiles and many terrestrial invertebrates, on the other hand, excrete ammonia as uric acid. These processes help organisms eliminate toxic ammonia and prevent its accumulation in the body.