Water Quality in Fish Ponds: pH, Carbon Dioxide, Alkalinity

What is the measure that indicates whether water is acidic or basic?

• Carbon dioxide

• pH

• Alkalinity

• Hardness

What is the recommended pH range for aquaculture?

• 0 to 14

• 6.5 to 9.0

• 5 to 10

• 7.0 to 8.0

At what pH level can fish become stressed and die?

• Below 5

• Above 10

• Between 6.5 and 9.0

• Between 7.0 and 8.0

What causes the pH of pond water to fluctuate throughout the day?

• Respiration and photosynthesis

• Carbon dioxide and alkalinity

• Hardness and oxygen availability

• Toxicity of ammonia and metals

What is the effect of high carbon dioxide concentrations in fish ponds?

• Direct toxicity to fish

• Decreased dissolved oxygen

• Increased blood pH

• Improved pond productivity

How can chronically high carbon dioxide levels be treated in fish ponds?

• Chemical treatment with hydrated lime

• Increasing dissolved oxygen concentrations

• Adding ammonia to balance pH

• Reducing alkalinity levels

What is the measure of the quantity of base present in water?

• Carbon dioxide

• pH

• Alkalinity

• Hardness

What is the desirable range of total alkalinity for fish culture?

• 0 to 14 mg/L

• 20 to 50 mg/L

• 75 to 200 mg/L

• 100 to 250 mg/L

What is the primary source of alkalinity in fish ponds?

• Carbon dioxide

• Rainwater

• Underground water

• Limestone

What is the role of calcium in fish culture water?

• Toxicity to fish

• Prevention of salt loss

• Increased ammonia levels

• Improved photosynthesis