There are many ways to increase the productivity of cultivation, there are many treatments or treatment also can be used. Giving lime is one of the common treatments to support pond productivity. Lime plays a direct role in shrimp growth and water quality management.
Types of lime commonly used in shrimp farming include agricultural lime/captan (CaCO 3 ), dolomite (CaMg(CO 3 ) 2 ), quicklime (CaO), and hydrated lime (Ca(OH) 2 ).
What are the functions of lime in shrimp ponds?
Raise pH
The degree of acidity (pH) plays a role in the physiological stability and metabolism of shrimp. The recommended water pH range for shrimp farming is 7.8-8.5. Lime has the main function of increasing the pH of water and soil. Lime works by binding hydrogen ions (H) thereby reducing the acidity of water and soil. Lime can be given directly to water, soil, or added to feed.
Increases alkalinity
Liming is also a solution for pond alkalinity that is too low. The alkalinity of shrimp pond water should not be less than 100 ppm. Alkalinity affects the stability of water pH and water fertility.
The increase in alkalinity controls the pH and calcium concentration. Sufficient alkalinity can maintain fluctuations between morning and evening pH in the range of 0.2-0.5. The pH fluctuation should not be more than 0.5. Changes that are too large or sudden cause the shrimp to go into shock and stop eating.
Helping the molting process
Giving treatment in the form of lime will provide a source of Ca (calcium) needed by the shrimp in the molting process (Also read: Full Moon and Molting Shrimp ) . The more often the shrimp molt, the faster the shrimp growth. One of the things that is needed to support it is to have sufficient minerals, especially calcium. Calcium is used in the formation and hardening of new shrimp shells.
Lime is applied by dispensing directly into the water or adding it to the feed. If added to the feed, lime will enrich the feed content as a source of minerals to facilitate the molting process of shrimp. Regulation of the Ca/P ratio in the feed also supports carapace calcium (skin) and feed efficiency.
Accelerate the process of decomposition of organic matter
This function is mainly intended for pond soils that are acidic. Acidic soil causes disruption of the nutrient cycle. Soil in shrimp ponds has the potential to become more acidic as a result of the accumulation of organic matter from feed residues and shrimp metabolism products (faeces). This will reduce the productivity of cultivation. The surrounding environment has an impact on the degradation of environmental quality. The decomposition of organic matter becomes incomplete.
Giving lime can also be a solution in ponds that have too concentrated water. Characterized by low water brightness. This is an indication of blooming algae . Giving lime can increase the penetration of sunlight, so that the brightness of the water increases. Lime will bind phosphate from water, mainly by calcium. The impact will limit the photosynthesis of phytoplankton. The next impact is that the pH of the water increases and carbon dioxide decreases.
Get to know the types of lime that can be used
Dolomite lime (CaMg(CO 3 ) 2 )
Dolomite lime is lime with high calcium and magnesium content. This type of lime is a source of minerals for vaname shrimp. Calcium and magnesium play a role in activating various types of digestive enzymes in shrimp and assisting the molting process.
Dolomite lime can be applied by adding it to the feed in a certain ratio. Dolomite serves to increase alkalinity and hardness. Dolomite is used when the alkalinity is low, the increase in the pH of the water is not too drastic.
Lime (CaO) and hydrated lime (Ca(OH) 2 )
The use of CaO and Ca(OH) 2 is not recommended. In addition to being more expensive, both cause a drastic increase in pH so that it can have a negative effect on shrimp. Hydrated lime can raise the pH and binding CO 2 effectively. To increase the alkalinity and at the same time raise the pH, lime hydroxide Ca(OH) 2 can be used, but the dosage must be considered.
Agricultural lime (CaCO 3 )
Agricultural or general lime also called kaptan has the main function of increasing pH, hardness, and alkalinity. Contains calcium which can bind H ions in water so that it effectively raises the pH. Giving captan in large quantities will also increase the alkalinity which plays a role in the stability of the pH of the water.
What is the right dose of lime in ponds?
Giving lime must be with several considerations and goals
- Know the current state of the pond. For example, first measure the pH range in the morning and evening, the frequency of molting, or the current concentration of alkalinity.
- Cultivation profile. For example by considering the area and depth of the pond (to determine the total volume of water) and also the stocking density of shrimp.
- The type of lime used is also adjusted for the purpose, only to increase the alkalinity or to increase the availability of calcium.
These things will determine the dose to be given. Because giving the right dose is needed so that the effects are also in accordance with the purpose. Lime will react more quickly by spreading it directly into the water. Lime will slowly dissolve, resulting in decreased alkalinity and hardness. So giving lime regularly is also needed taking into account the conditions.
