Algae are one of the most suitable algae in terms of size and nutritional quality for black tiger shrimp larvae. Algae are fast-growing, can be cultured under artificial conditions, in hatcheries. Through the production and research, two types of silicas (Baciliariophyta) were found to feed biomass and feed the larvae.
Chaetoceros sp and Skeletonema costatum are two strains of algae, ranging in size from 4-6μm. Surface cells are rectangular or square, at the corners of the spines or short bristles, and these spines and hairs cause the algal blooms to bind together into strings (Skeletonema 20-50tb / string.) Chaetoceros 10 -20tb / string). Algae are a phytoplankton present in brackish water, saltwater, with concentrations of 0-50 ‰. The algae on a wide temperature range are suitable for temperatures between 25 – 300C. Intensity of light is especially important for the growth and development of algae under the conditions of culture, the lighting time is over 12 hours after about 20 – 24h algae grows at the density of 500,000 to 600,000tb / ml. . Under favorable environmental conditions, adequate nutritional quality, the development of Chaetoceros and Skeletonema make the water yellowish green to brown. Biomass grows through four phases.
1.1 Phase delay:
Sometimes extended due to the suitability of the new algae’s poor nutritional environment and the cell death.
1.2 Growth phase:
Characterized by continuous cell division according to formula X x 2n
(X is the number of reproductive cells X ≥ 1, n number of spawns (n ≥ 1))
1.3 Phase stop
Characterized by the balance between the growth of new cells and the less dead cells.
1.4 Phases of Death:
This is the result of the elimination of nutrients to the point that they do not sustain development or can also die of waste in the process of living.
2 Method to breeding
– cell division.
– formation of the prince.
2. Culture technology:
– racquets (racquets, racquets)
– Cord Ø 21 or 27
– Wind, pumice stone
– Breeding tanks (glass vase, or triangle)
– biomass basins (from 1-3m3 / tank)
– Chemicals of all kinds
Use Walne medium to culture and feed algae biomass
The solution in the following order:
Solution 1 (Growth)
– KNO3 (or NaNO3) 116gr (100 gr)
– EDTA 45.0 gr
– H3BO3 33.6 gr
– NaH2PO4.2H2O 20 gr
– FeCl3 1.3gr
– MnCL2.4H2O 0.36gr
– Solution 2 (micro minerals) 2,1gr
– CoCL2. 6H2O 2.0gr
– Dissolve in 100ml of fresh water
Solution 3 (vitamin)
– B1 200mg
– B12 100mg
– Dissolve in 100 ml of fresh water
* Solution 4 (extra solution)
– KNO3 100gr
– Dissolve in 1 liter of fresh water
Solution 5 (silicate environment)
– Na2SiO3.5H2O 20gr (or 67ml)
– Dissolve in 1 liter of fresh water
For each medium used in culture, each solution (1, 3, 5, 5, 5) in a ratio of 1/1000 (1 ml of each solution per 1 liter of water). When used to feed biomass, apply the solution on the scale of 1 / 10.000.
Water source:The water used for culture and culture of algae must be treated (see Water Treatment Technology).
Collection technique, pure breed, breeding:
– Seed collection techniques:
The varieties are picked up in coastal areas at high tide, using a net mesh of 15-18μm mesh size, as shown in figure 8. For species to be collected we have to collect samples several times. Under the microscope we examined Chaetoceros sp and Skeletonema in string form.
Reciprocal algae naturally contain many organic humus and zooplankton. Therefore, we have to isolate the algae with a mesh size larger than the pass through several times and finally retain only the algae water in it.
It is possible to implement the puree of algae in two ways:
– Use the environmental advantage to be purely relative. It means that in conditions of nutrient environment to be in line with the developmental biology of these two algae will help them prioritize development. Over time, these two varieties of algae will dominate the population and become purebred.
– Use the isolation method to separate the two algae varieties to feed separately with appropriate nutritional environment. After many times they will become purebred.
– When pure-bred algae are kept and raised for biomass.
Breeding:To actively provide algae for production, we need to have algae storage methods. Algae retention is carried out in the algae culture room or in the isolated area of the algae culture or in the hatchery. The variety is kept in glass vase or triangular vase and grown in Walne medium at 25-30 n. The culture time depends on the initial algal density and the growth of algae. Normally, algae culture time is from 16-24h. This way of keeping can ensure the quality of algae before being fed to biomass.
Biomass Farming Techniques:
In shrimp hatcheries, it is usual to start feeding algae biomass when Nauplius (N) larvae are at N3 or N4 stage. The biomass culture is carried out in the following steps:
– Thoroughly clean the aquarium with soap and then rinse it off with the treated seawater
– Pumping seawater into the tank
– Gas supply (24h / 24h)
– The level of algae (stored variety) is in the growth phase with a loss of 50,000-70,000tb / ml.
– Serve the nutrients (in the mix) in the order of the prepared solution (note the solution 5 usually or precipitate with salt water, so for this solution we need to add fresh water). On shady, sunny days, shade can be increased to 5 times.
– When the algae in the biomass aquarium reaches the density of 500,000 – 600,000tb / ml or with the naked eye, we can see the dark brown algae is able to collect biomass.
* Method: Use plastic wire Æ 21 or larger depending on the flow, one end is tied by net bag (net mesh size 15 – 20μm) the other end into the light suction pool, algae water will flow continuously in the interval. For 15-30 minutes, the algae cells are retained, then the bag is removed and the algae is transferred to the bucket, and then collected again until the water in the algae tank is about 1 / 4-1. / 5 may end.