Aquaculture Systems

Current Events:

A vaccine for Ich

Types of systems

• Cage

• Raceway

• Pond

• Recirculating Tanks

Cage

• Can move cage to fresh water

• Fish can escape

• Fish can be stolen/released

Movie

Raceway

• Need constant flow of water

• Generally built parallel to rivers

• Necessary for trout

• High water quality

Pond

• Most common method

• Large scale production

• Lowest maintenance

Recirculating tanks

• Uses least amount of water

• Best Temperature control

• Lowest water quality

Recirculating Tanks

• Main Tank

• Bio Filters

• Sediment Tank

• Pumps

• Water in/out control

Main Tank

• Holds fish

• Creates circular water pattern

• Collects from the bottom

• Removes Sediment/waste

Biofilter

• Plastic substrate that bacteria can cling to.

• Bacteria convert toxic ammonia (NH3) in fish waste to nitrite (NO2) and then nitrate (NO3) which is least toxic.

Biofilter

• Bacteria (Nitrosomonas & Nitrobacter) cling to plastic discs

• Aerobic Bacteria• Bacteria control the Ammonia• Takes 2-4 weeks for colonization

• Ammonia →Nitrite →Nitrate• NH3 & NH4

+ →NO2 →NO3

• Most toxic → Least toxic

Sediment Tank

• Has a cone shaped bottom

• Non-soluble solids settle out

• Soluble solids – give the water a brown color – need special filters

Sand filter

• Removes solids

• Sand clogs quickly

• Must backwash daily

• Residue build-up– No longer functional

Aquaculture Tanks

Aerators

• Keep the water circulating

• Keep oxygen in the water so fish do not suffocate.

Equipment

• Seines – nets with predetermined opening sizes to catch or hold only fish larger than a specific size

Shrimp Harvest

• Video