What do Fish Want??What do Fish Want??

The importance of Water The importance of Water QualityQuality

and Testing Waterand Testing Water

Topics of ImportanceTopics of Importance

Components of WaterComponents of Water What do fish really want??What do fish really want?? AmmoniaAmmonia NitritesNitrites NitratesNitrates Dissolved OxygenDissolved Oxygen

Components of WaterComponents of Water

Key nutrient ions Key nutrient ions Phosphates, nitratesPhosphates, nitrates

Dissolved GasesDissolved Gases Oxygen, Carbon dioxideOxygen, Carbon dioxide

Trace ionsTrace ions Copper, iron, zinc, etc.Copper, iron, zinc, etc.

What do Fish Want??What do Fish Want??

Low ammonia and nitrate levelsLow ammonia and nitrate levels Chemically clean waterChemically clean water Correct water pH and temperatureCorrect water pH and temperature Low levels of organic pollutionLow levels of organic pollution Stable conditions in waterStable conditions in water

Ammonia and Water Ammonia and Water QualityQuality

Ammonia is extremely toxic and even relatively low levels pose a threat to fish health.

Fish continually excrete ammonia directly into the surrounding water via special cells in the gills.

In a natural environment, such as seas, lakes and rivers, it would be immediately diluted to harmless levels.

However, in ponds, levels can rapidly rise to dangerous levels unless it is constantly removed, usually by biological filtration.

Additional amounts are produced from decomposing fish food and fish waste

Irritates gills, restricting the water flow over the gill filaments, respiratory problems and stress

Rub against solid objects, without water testing it would be very easy to wrongly conclude the fish had a parasite problem.

The fish response to toxic levels loss of appetite, laying on the pond bottom with clamped fins, or gasping at the water surface if the gills have been affected.

Nitrites and Water QualityNitrites and Water Quality

Nitrite (NO2-) is formed when bacteria

oxidizes ammonia produced by fish and decomposing organic matter.

Prolonged exposure to low levels can lead to stress, ulcers and fin rot

The main danger: transported across the gills and into the fish’s bloodstream, unable to move nitrates and fish suffocates

At low levels the fish may rub against solid objects or ‘flash’, gills will be pale tan to dark brown in color, gasping at the water surface.

Nitrogen cycle changes nitrites into nitrates, 2000 times less toxic to trout

Dissolved Oxygen and Dissolved Oxygen and Water QualityWater Quality

Process of photosynthesis effects Process of photosynthesis effects amount of oxygen in water (20 - 30 amount of oxygen in water (20 - 30 times less in water than air)times less in water than air)

CO2 + Water ----> sugar + O2 + H20CO2 + Water ----> sugar + O2 + H20 As temperature increases, DO As temperature increases, DO

decreasesdecreases Causes decrease in growth and Causes decrease in growth and

reproductionreproduction

Solutions to low level:Solutions to low level:– Stop feeding to increase organic Stop feeding to increase organic

materialmaterial– Change partial waterChange partial water– Decrease temperature slowlyDecrease temperature slowly