Once feeding starts, wasted, uneaten food, can foul the water and lead to fish health problems such as bacterial gill infections. Bacterial gill disease can be lethal. This is of special concern as the fish start to feed train.

The key to keeping the water clean is to feed only enough food so that it is all eaten immediately. Feed that falls to the bottom will not be eaten by the fish and can dissolve in the water causing it to become cloudy. The uneaten food is a nutrient that can promote the growth of harmful bacteria.

Signs of fouled water include cloudiness and suspended particles of food and feces. Uneaten food and feces should be siphoned out of the tank daily. If the water becomes cloudy it should be replaced.

Clear, apparently clean water can have harmful levels of ammonia. Ammonia is a metabolic product the fish produce as they eat and grow. Ammonia levels should be monitored with a simple test kit. When the levels approach 0.0125 parts per million you should stop feeding the fish and replace the water.

Always keep in mind that salmon naturally inhabit clean flowing water. They do not tolerate poor water quality and will become sick and die if the water quality is not maintained.