Pond Water Quality

1. Pond Water Quality (the basics) Frank Henning UGA Watershed Extension Agent

2. To a great extent water quality determines the success or failure of a fish operation

3. Fish live in water • Eat • Breathe • Excrete wastes • Reproduce • Take in and lose salts

4. Water Quality Factors • Temperature • Oxygen/CO2 • Alkalinity, Hardness & pH • Nutrients (NH3 and P) • Sediment

5. Dissolved Oxygen • Importance • highest cause of mortality • Safe levels • greater than 5 mg/L • Dense bloom, bloom die-off herbicide app. & turnover

6. Daily O2, CO2 Cycles

7. DO Management Avoid Overfeeding Maintain Proper Densities Avoid Over-fertilization Intelligent Weed Control Monitor Inflow Quality

8. Outlet Design

9. Signs of Low DO • Fish not eating • Piping & Gasping • Groups of Fish at Inflow • Poor Growth • Frequent Disease/Parasite Outbreaks

10. Projected Dissolved Oxygen Levels 7 Measured values 6 5 mg/l 4 Lethal Projected values 3 2 1 0 5 pm 10 pm 5 am

11. Problem Suspected Monitor DO Provide Aeration & Circulation

12. Temperature • Effects • metabolic rate doubles for every 18oF increase • Influences spawning • Influences growth • Water Density • Max @ 39o F • Turn- over Fish Categories – coldwater – coolwater - warmwater

13. pH • Measure of the hydrogen ion concentration • 1-14 scale • less than 7 acidic • greater than 7 basic • Safe range • 6.5 - 9

14. Hardness • Hardness if the measure of divalent cations • calcium • magnesium • Hardness is used as an indicator of alkalinity but hardness is not a measure of alkalinity • magnesium or calcium sulfate increases hardness but has no affect on alkalinity • Recommended hardness levels > 20 ppm

15. Alkalinity • Alkalinity is the capacity of water to buffer against wide pH swings • Acceptable range 20 - 400 mg/L

16. Liming Ponds Total Alkalinity > 20 ppm Agricultural Lime ~ every 2 – 4 years Broadcast Over the Entire Pond Surface Professional Liming Barges on Large Ponds

17. Guidelines for Application of Lime in Ponds 12 mg/l 1-2 ton 12 - 14 mg/l 1 ton 15 - 25 mg/l 1/2 ton 25 mg/l or more None Total Alkalinity Lime/Surface Area

18. Proper Fertilization • 5-10 apps per year • Start in February • Time apps using secchi disk • Shade out weeds

19. Fertilization Supplements the Food Chain More Fish - Not Bigger Fish Multiplies the Base of the Food Chain Increases Carrying Capacity 4X

20. Professional Disk $25 • Measures visibility • Measure frequently • Pie pan, 5 gal bucket lid w/ weight. Using the Secchi Disk

23. Granular Fertilizer Applications Usually applied using a platform Upper end of pond

24. Liquid Fertilizer Applications Tip # 1 - Dilute the fertilizer with water. Tip # 2 - Use small bilge pump. Tip # 3 - Pump or pour into prop wash. Tip # 4 - Cover the entire pond.

25. Water Soluble Fertilizer New trend Easy to apply Fast results

26. The Nitrogen Cycle Food Water plants Excess food Algae Fishes Feces Nitrate (NO ) Urine 3 Peptides Amino acids Urea Nitrite (NO ) Ammonia (NH ) 2 3

28. Management for N Problems • Reduce Densities • Avoid Overfeeding • Water Changes • Aeration • Salt

29. Clearing Muddy Ponds Step # 1 - Find the Cause Undesirable Species Poor Watershed Management Undesirable Water Source Step # 2 - Evaluate Solutions Total Renovation of Population Watershed Vegetation Chemical Alternatives Step # 3 - Implement Management Plan Establish vegetation in the watershed Lime pond, 200-500 lb Gypsum, Alum

30. Phosphorus • Limiting nutrient • Animal waste • Monitor nutrient input • >0.1 ppm (0.05 ppm)

31. Test Kits • Turbidity (Secci) • DO • Ammonia • pH • Temp • Alkalinity • Hardness

32. Lab Analysis (UGA Extension) • Alkalinity • Hardness • Phosphorus 1.800.ASK UGA1

33. More Information http://srac.tamu.edu/ http://county.ces.uga.edu/habersham/aqua/pondmanagement.html