Chemicals used in aquacutlure

1. Chemicals used in
Aquaculture
Presented by- Jyoti Saroj
Department.- Fisheries Resource
Management
College of Fisheries, Veraval, Gujarat

2. Introduction
Chemicals are essential for-
 Control of pathogens and diseases.
 Increased and controlled production of seed in
hatcheries, increased feeding efficiency and
improvement of survival rates.
 Production efficiency increased and animal welfare
enhanced

3. Chemicals used in aquaculture
Disinfectants-
 Hypochlorite(Sodium or calciumhypochlorite)
• Used for disinfection of tanks and equipment.
• Chlorine decays with time by the action of sunlight
and consumption of chlorine through its oxidation
of organic matter.
 Quaternary Ammonium compounds
(Benzalkonium chloride)
• It have detergent and antibacterial activity
• Widely used in shrimp ponds
• Now only limited use in food fish

4. Chemicals used in aquaculture
Disinfectants(conti.)
-EDTA
• Added to larval rearing water in some shrimp
hatcheries
• Reduce the bioavailability of heavy metals .
-Lime
• Widely used to neutralise acidity, increase total
alkalinity
• Lime applied to the pond bottom during pond
preparation at 100-8,000 kg/ha

5. •Burnt lime also used (at 50-100 g/m2) in
conjunction with ammonium phosphate to kill pests
and predators.
Lime applied in pond

6. Chemicals used in aquaculture
Feed additives (Sulfonamides)
– Sulfamerazine and Romet-30
• Effective for bacterial infections
• 220 mg/kg fish for 14 days.
• Some treatments recommend 3 days, fewer
side-effects.
– Toxicity may occur -
• Kidney damage (drug crystal formation in
renal tubules)
• Clinical signs – bloating/dropsy (stomach full
of water)

7. Chemicals used in aquaculture
Continued-
– Romet-30
• Suggested dose (furunculosis) – 50mg/kg
fish/day for 5 to 7 days
• Also effective for ESC
• Still used in the catfish industry.

8. Chemicals used in aquaculture
Terramycin (oxytetracycline) – TM50
 Effective against gram neg. bacteria and gram
positive bacteria.
Recommended dose – 55-83mg/Kg fish/day for
10 days
Should not be fed on prophylactic basis!
• Resistance to oxytetracycline can occur in most
bacterial fish pathogens

9. Chemicals used in aquaculture
Therapeutants added to water
– Methods
• Static bath – most reliable for
raceways/tanks
• Constant flow – safe and can be used in most
situations when fish reared in running water
Chemicals
 Formalin
• Employed as an antifungal agent
• Used to control ectoparasites
• 15 to 250 ul/l used for fish and crustaceans

10. Chemicals used in aquaculture
Chemicals (cont.)
 Potassium Permanganate
• Great for fungus!!
• Strong oxidizing agent
 NaCl (salt) (uniodized!!)
• Most overlooked treatment
• Can be very effective
• 3% recommended if possible (10-30 min)

11. Chemicals used in aquaculture
Copper Sulfate (<6.4 mg copper/L water)
– Also called Cutrine
– Algaecide/bactericide/parasiticide
• Effective on scaled fish, but can cause
problems with scaleless fish (catfish).
• Can produce kidney necrosis, destruction
of hematopoietic tissue, increased liver fat
and inhibition of digestive enzymes.

12. Chemicals used in aquaculture
Malachite green
• Global use as an antifungal and antiprotozoal
• Its use is not permitted in the USA and some
Southeast Asian countries.
Methylene blue
• Effective against fungal and protozoan infections
• May also provide protection against nitrite
intoxication