EFFECTS OF ALKALINITY ON GROWTH AND SURVIVAL RATE OF MARINE SHRIMP LARVAE AND POSTLARVAE

This article is a study by Dr. Chau Tai Tao (Faculty of Fisheries - Can Tho University) on the effect of alkalinity on the growth and survival rate of black tiger shrimp and whiteleg shrimp larvae and postlarvae.

What is alkalinity?

• Total alkalinity indicates the acid-neutralizing capacity of water.
• Alkalinity in water is created by 3 ions: OH^-, CO₃^2-_, HCO₃^-. Among these, HCO₃^- is the main form.

Effects of alkalinity:

• Alkalinity affects the buffering system in the aquatic environment.
• It maintains pH fluctuations and helps stabilize water pH.
• Changes in water alkalinity will affect physical and chemical factors, as well as the survival rate and growth of shrimp.
• In marine shrimp larval rearing, lower alkalinity makes it difficult for shrimp to harden their shells after molting. If alkalinity is too high, shrimp larvae and postlarvae grow slowly, have difficulty molting, or fail to molt, leading to death.

Experiment evaluating the effect of alkalinity on the growth and survival rate of black tiger shrimp and whiteleg shrimp larvae:

Experimental setup:

• Shrimp rearing water salinity 30‰.
• Soda (NaHCO₃) was used to adjust alkalinity to suit each treatment before larval stocking.

The experiment included the following treatments:

• For the black tiger shrimp experiment: Larval rearing water alkalinity of 80, 100, 120, 140 mg CaCO₃/L corresponding to treatments 1, 2, 3, 4.
• For the whiteleg shrimp experiment: Larval rearing water alkalinity of 100, 120, 140, 160, 180 mg CaCO₃/L corresponding to treatments 1, 2, 3, 4, 5.

Monitored parameters:

Environmental monitoring: Temperature, TAN, NO₂^-, alkalinity.

Shrimp monitoring:

• Total length of larvae and postlarvae was measured at stages Z₃, M₂, PL₁, PL₅, PL₁₀, PL₁₅ (for black tiger shrimp) and Z₁, M₁, PL₁, PL₆, PL₁₂ (for whiteleg shrimp).
• Survival rate was determined at PL₁₅ (for black tiger shrimp) and M₁, PL₁, PL₁₂ (for whiteleg shrimp).

Results:

Table 1. Environmental parameters in the black tiger shrimp experiment

Parameter		Treatment
		80 mg CaCO3/L	100 mg CaCO3/L	120 mg CaCO3/L	140 mg CaCO3/L
Temperature (°C)	Morning	29.6 ± 0.21	29.2 ± 0.22	29.2 ± 0.12	29.3 ± 0.24
	Afternoon	30.6 ± 0.52	30.6 ± 0.59	30.5 ± 0.58	30.6 ± 0.6
pH	Morning	7.9 ± 0.03	7.8 ± 0.0	7.9 ± 0.02	Quick Q&A Frequently asked questions on this topic What does "EFFECTS OF ALKALINITY ON GROWTH AND SURVIVAL RATE OF MARINE SHRIMP LARVAE AND POSTLARVAE" cover? Alkalinity affects the buffering system in the water environment, mitigating pH fluctuations and helping to stabilize water pH. When water alkalinity changes, it will affect physicochemical parameters, survival rate, and shrimp growth. Which species does this article apply to? Shrimp — Water & environment Related Products Products linked to this topic ShrimpThan Vuong Blue PRO GUT Premium digestive probiotics specifically for shrimp farming in lined ponds Shrimp Read tom / ca / ocThan Vuong Blue MAX 4000 Probiotic that helps reduce the toxic gases NH3, H2S and NO2 tom / ca / oc Read ShrimpThan Vuong Blue HERB GUARD Enhance liver function, improve color of hepatopancreas Shrimp Read More Reading Related technical articles Research Insight•Shrimp•February 28, 2026 CHANGES IN GUT MICROBIOTA DUE TO GLOBAL WARMING. REGULATING HOST HEALTH AND DISEASE STATUS IN POIKILOTHERMIC ANIMALS Global warming alters the gut microbiota of Pacific whiteleg shrimp by restructuring enterotypes, increasing the risk of diseases su[...] Read Protocol•Shrimp•February 23, 2026 Minimizing Risks Lies in a Systems Management Approach In modern shrimp farming, there's a rather "painful" reality that many farmers still haven't accepted: Risk mitigation doesn't lie i[...] Read Protocol•Shrimp•January 29, 2026 TREATMENT PROTOCOL FOR YELLOW MOUTH DISEASE IN WHITELEG SHRIMP Yellow mouth disease (often accompanied by yellow gills) is an indication that the pond environment is at low salinity (5ppt) or exp[...] Read Ask Than Vuong Aquaculture technical assistant Hello there 👋 Describe your pond issue or pick a question below. Two-tone, broken faecal strands?High NO2 — what to do?Weak appetite, slow growthHow to raise alkalinity? Send