There most assuredly is going to come a time in the life of every hobbyist when their fish get sick and treatment becomes the only solution for saving them. Sometimes, even after the most careful approach, the success rate is dismal. You would be understandably upset if this occurs, and would like to know the reasons why your medications didnít work. In a large percentage of these failures we can usually determine the likely reasons and, for the vast majority of these failures, we can offer some guidelines as to the cause. Here are what we have ascertained as the major causes of "failed" treatments.
Most fish disease
problems coincide with poor water quality, and should not be treated
until water quality has been corrected.
Poor water quality, such as a low pH value, high ammonia, or nitrite level, may be the "stress" factor that weakens your fish and makes them vulnerable to attack by various parasites and diseases.
At the first signs of discord with your fish you should immediately check your water quality and make any changes necessary to get the parameters corrected. Remember that while medications such as antibiotics and anti-parasitic drugs are destroying the bad bacteria or parasites that are harming your fish, they do not discriminatebetween bad or good, and will also destroy the beneficial bacteria in your aquarium that are keeping your water quality parameters, such as ammonia and nitrite, in check. Treating a tank with poor water quality only increases the stress on the fish and negates the effect of the treatment, and further decreases the water quality.
A wrong diagnosis has
Treatment has been instituted, but the protein skimmer, and/or charcoal filtration has beencontinued.
Depending on the efficacy of the skimmer and the amount and quality of the charcoal, much of the active ingredients of the treatment will be removed, ensuring a negative result.
Many aquarists are
unsure about the amount of water in their tank, and often forget to
include in their treatment calculations the water in their sump, etc.
Also they sometimes do not allow for the water displaced by large
amounts of live rock, etc.
The fish are in an
advanced stage of infection before treatment is started.