Here is an excellent article showing that more is not better.
There are no easy answers to every fish disease treatments. Sometimes it takes a lower dose, plus a number of other measures for more effective and successful treatment.
In the above article, the experienced farmers usually have an aquatic veterinary team to help them navigate through fish disease issues, and to avoid nasty disasters where the cure is worse than the disease.
At The Fish Vet, no two clients ever have the same treatment regimen, because all cases are unique. We account for factors such as host species, water parameters, pathogen/s, historical data, and our first-hand local experience. Our veterinarians are based across Australia, in Perth, Melbourne, Sydney and Canberra.
Watch some examples of the diverse problems we encounter at – http//tinyurl.com/thefishdoctor