Lesson 3 - Water Quality

Question 1

It determines the success or failure of fish culture

Answer 1

Water quality

Question 2

Importance of water quality

Answer 2

1. Fishes live in water
2. Fishes are supported by water
3. Fishes receive oxygen from water
4. Fishes exercise in water
5. Its factors influence and interact with each other
6. What may cause problem in one situation may be harmless in another
7. It influences effectiveness/toxicity of treatments
8. Most disease problems can be avoided with proper management of water quality
9. It includes maintaining water quality at a level that provides an environment conducive to fish health and growth

Question 3

Water quality variables

Answer 3

1. Temperature
2. Dissolved oxygen
3. Total ammonia-nitrogen
4. Alkalinity
5. Hardness
6. pH
7. Carbon dioxide

Question 4

It controls the reaction rate of chemicals

Answer 4

Temperature

Question 5

Influences the solubility of gases in water

Answer 5

Temperature

Question 6

Influences toxicity of ammonia and therapeutants

Answer 6

Temperature

Question 7

Optimum temperature for tilapia growth

Answer 7

85-88 F

Question 8

For each _____ rise in temperature, the metabolic rate doubles

Answer 8

10C

Question 9

First limiting factor for growth and fish health

Answer 9

Oxygen

Question 10

Solubility decrease with increasing temperature and elevation

Answer 10

Oxygen

Question 11

Respiratory rate increases with increasing temperature, activity and feeding

Answer 11

Oxygen

Question 12

In general, the minimum _____ should be>60% of saturation or > 5ppm

Answer 12

DO

Question 13

2 ppm in biofilter effluent

Answer 13

Oxygen

Question 14

Usually the second limiting factor-nitrogenous waste:feces and feed

Answer 14

Total ammonia-nitrogen

Question 15

It includes ammonium ion and ammonia

Answer 15

TAN

Question 16

The proportion of NH3 increases with increasing temperature and pH

Answer 16

Total Ammonia-Nitrogen

Question 17

Is the buffering capacity of water - absorbs acids and/or bases

Answer 17

Alkalinity

Question 18

Prevents with all fluctuatons

Answer 18

High alkalinity

Question 19

Hardness (water quality variable)

Answer 19

50-100 mg/L

Question 20

pH (water quality variable)

Answer 20

7-8

Question 21

Carbon dioxide (water quality variable)

Answer 21

<20 mg/L

Question 22

Total dissolved gasses, supersaturation caused by:

Answer 22

1. Leaking water lines
2. Air leak on low pressure side of pump
3. Sources of water
4. Mixing cold and hot water

Question 23

Recommended total dissolved gas pressure

Answer 23

<104%

Question 24

Stressors:

Answer 24

1. Poor water quality
2. Environmental conditions
3. Improper handling

Question 25

Most fish disease are

Answer 25

Stressed mediated

Question 26

Is a physiological state caused by a procedure, environmental condition or other factor which interferes with he ability to maintain a “normal” state.

Answer 26

Stress

Question 27

It extends the adaptive responses beyond the normal range or which disturbs the normal functioning

Answer 27

Stress

Question 28

The first sign of water quality/environmental problems

Answer 28

Low level mortality

Question 29

Loading effects

Answer 29

1. DO level
2. Metabolic rate of fish
3. Amount being fed
4. Pathogen load
5. Water exchange rate