Managing Fish Ponds

During a DroughtGary Burtle

Animal & Dairy ScienceUniversity of Georgia

Tifton, GA

What happens to your pond in a

drought?

Water level drops

Seepage increases

Oxygen depletions

Muddy conditions

Weed problems

Fish Diseases

Pond dries up

Low Water Exposes Pond Bottom

Pond Design

Is the pond soil able to hold water?

Was the dam properly compacted?

20 acres of Watershed per Pond Acre

–Follow spillway design for wet weather overflow

Supplemental Water Source?

–Do not drill a well.

Is the pond deep enough?

–8 to 10 feet is best

Soils

Need at least 25% clay, but 35% is better

No sand, gravel, or rock outcrops

Pond bottom should be clear of vegetation and compacted

Compaction

Pond dams are compacted every 12 inches as they are built

Compact around drain pipes

NOTE: Excavated ponds are not compacted, so seep freely, exchanging water with the water table.

Watershed and Depth

10 to 20 acres per Pond Acre

Plan for a minimum of 3 feet of water and two to three feet of water loss during the drought

Seepage Problems

Low clay content

Seeping under dam or around pipes

Rock outcrop

Check the Soil TexturePhoto from L. Swann

Collect a sample of moist soil

Make a golf-ball-size ball

Squeeze a ribbon between thumb and forefinger

¾ inch = 25-30% clay

Bentonite

Sand and Rock

Cover with a 1 to 8 ft layer of clay

Pour Bentonite crystals directly over the leak

Excavate and fill hole with clay

Digging the Pond Deeper?

Be careful when enlarging a pond

Don’t dig through the clay layer

Don’t expose rock or sand

Compact after digging

Oxygen and Drought

Low water level

Hot water

Dense algae bloom

Crowded fish population

Prepare to Aerate

Aerators

Diffusers

Algae

Algae Control

Treat Early with an algicide–Copper sulfate or Liquid copper chelate

–Reward or Hydrothol

–Sodium Percarbonate

– (Water gardens use Algaefix)

Stock grass carp at 10 or more per acre

Aeration may help with most algae, will actually increase Lyngbya

Duckweed and Watermeal

Controlling Duckweeds

Stingray (carfentrazone) – 13.5 oz/A

Reward:Cutrine-plus (2:1 tank mix)

Use sticker/spreader with spray

–Cide Kick II, Topfilm, PolyAn

Aerate

For watermeal, use Sonar or Reward

Muddy Water

Correct the source of turbidity

Lime

Add clearing agent

–Alum

–Gypsum

–Organic material

Drought Management

Proper Pond Design

Manage problems early

Reduce fish populations

Repair pond if it dries up