Pond Management

(Establishing a Pond)

Water Quality

Fish and livestock don’t mix

pH

• pH indicates whether water is acid, neutral or base

• A range of 6.5 to 9.0 is desired for aquatic life

Fig. 2. pH scale showing recommended range (Wurts & Durborow, 1992).

A pH of 7 is neutral, pH < 7 is acidic , pH > 7 is basic (alkaline).

0

4.0

7

9.0 11

14

6.5

pH

Death DeathDesired range for

aquaculture

AlkalinityIf I could teach one thing …

Total Alkalinity

• Measures how much base is present in water

• Affects pH, copper toxicity & availability of phosphorus

• Must be above 20 ppm (mg/L)

Alkalinity & pH

• Low pH is common with low alkalinity

• Increasing alkalinity increases pH

• Alkalinity stabilizes pH

Changes in pH during a 24-hour period in waters of high and

low total alkalinities (Wurts and Durborow, 1992).

pH

High alkalinity water

Low alkalinity water

11 -

10 -

9 -

8 -

7 -

6 -

5 -

Early

Morning

Early

Morning

Late

Afternoon

Liming

• Adding ag. limestone will increase alkalinity, pH & phosporusavailability

• Collect soil samples from pond bottom, to a depth of 6 inches

• Send samples to soil testing lab

• Use recommendation for “Alfalfa”

Warning: Avoid Using

• Hydrated & Quick (Slaked & Burnt) Lime

• These compounds can cause sudden, large increases in pH

• Rapid pH changes can kill fish

Benefits of Liming

• Helps prevent wide swings in pH

• Adds Ca & Mg to water

• Improves safety for using copper

• Enhances effect of fertilizer, phosphorus

Aquatic Food Chain

• Phytoplankton

• Zooplankton

• Small Insects

• Small Fish (minnows & bluegills)

• Large Fish (bass & catfish)

Fertilization

• Lime to improve nutrient availability first

• General 30 lb/ac @ 2 week interavals (x 3)

• Use Secchi Disk

• Long-term commitment

D.O.

Daily Oxygen Cycle

Early

Morning

Early

Morning

Late

Afternoon

12.0 -

10.5 -

9.0 -

7.5 -

6.0 -

4.5 -

3.0 -

Dissolved Oxygen

Pond Construction

• Clay soil, at least 20%

• No less than 2.5-3 ft deep (weeds)

• No more than 8 ft deep (turn-over)

• Evaporation – well vs. watershed

• Avoid floodplain

Fish Species for Ponds(< 50 ac)

• No – Crappie, Green Sunfish

(Hybrid Sunfish?), Flathead Catfish, Bullheads, Golden Shiner

• Yes – Largemouth Bass, Bluegill

Sunfish (Redear ?), Channel Catfish, Triploid Grass Carp

Fish Stocking Calendar(New Pond)

• Bluegill Sunfish: Early Fall (Sept/Oct)

• Channel Catfish: Early Spring (mid-April) of the following year

• Largemouth Bass: Late Spring (1st

half of June) of the following year

Aquatics Weeds

• Weeds are not the problem

• Weeds are the symptom

• Conditions favoring plant growth

• Fix the problem or weeds will return

Aquatic Plants/Herbicides

• Algae – copper, endothall

• Submerged – diquat, endothall

• Emergent – glyphosate, imazapyr

• Floating – fluridone, diquat, glyphosate

Grass Carp

• Soft-stem, submerged plants

• 7-10 fish/ac for new pond

• 10-15 fish/ac for moderate weed problem

• Stock 10”-12” grass carp if large bass are present

Aquatic Weeds

Filamentous AlgaeMoss, Pond Scum

Bluegreen Algae

Chara(an alga)

Duckweed

Watermeal

Southern Naiad

Water Primrose

Variable Leaf Pondweed

Spatterdock(Water lily)

Cattail

Willow

Look Alikes

1

2

3

Look Alike ID

1. Coontail

2. Slender or Spiney-Leaf Naiad

3. Chara

Slide Shows On-line www.ca.uky.edu/wkrec/WurtsPrespage.htm

On-line Literaturewww.ca.uky.edu/wkrec/WurtsLitpage.htm

ExtensionAquacultureSpecialist

Dr. Bill WurtsKentucky StateUniversity CEP