Jurnal Akuakultur Indonesia 24 .
, 233Ae243 .
DOI: 10.
19027/jai.
Original article Utilization of skipjack tuna Katsuwonus pelamis offal waste for mass culture of Daphnia sp.
as feed for Betta sp.
Pemanfaatan limbah jeroan cakalang Katsuwonus pelamis untuk kultur massal Daphnia sp.
sebagai pakan ikan cupang Betta sp.
Indra Cahyono1*.
Sri Nurul Mutmainah2.
Buana Basir2.
Ardi Eko Mulyawan2.
Sri Mulyani3 Aquatic Resource.
Balik Diwa Institute of Maritime Technology and Business Makassar, 90245.
Indonesia Aquaculture.
Balik Diwa Institute of Maritime Technology and Business Makassar, 90245.
Indonesia Aquaculture.
Faculty of Agriculture.
Universitas Bosowa.
Makassar 90232.
Indonesia *Corresponding author: indracahyono@itbm.
(Received December 19, 2024.
Revised February 6, 2024.
Accepted May 22, 2.
ABSTRACT This study aims to assess the impact of skipjack tuna (Katsuwonus pelami.
offal soaking water on the mass culture of Daphnia sp.
for the growth of Betta fish (Betta sp.
This study was conducted for 30 days with treatment of offal 4.
5 ml/L .
reatment B), 7.
5 ml/L .
reatment C), 10.
5 ml/L .
reatment D), and commercial feed without skipjack offal soaking water as control .
reatment A).
The data variables of this study consisted of growth rate and population density of Daphnia sp.
, which were analyzed using variance analysis.
The results showed that the highest population growth rate was found in the treatment of offal soaking water 4.
5 ml/L with a value of 11.
and a density of 260 individuals/liter on the 19th day of rearing.
Daphnia sp.
produced from soaking tuna offal can also be used as a natural food for the growth and development of Betta fish, although its effectiveness is still lower than other organic materials.
Keywords: Daphnia sp.
, growth, mass culture, skipjack offal
ABSTRAK
Penelitian ini bertujuan untuk mengetahui pengaruh air rendaman jeroan ikan cakalang (Katsuwonus pelami.
pada kultur massal Daphnia sp.
terhadap pertumbuhan ikan Betta (Betta sp.
Penelitian ini dilakukan selama 30 hari dengan perlakuan air rendaman jeroan ikan cakalang sebanyak 4,5 ml/L .
erlakuan B), 7,5 ml/L .
erlakuan C), 10,5 ml/L .
erlakuan D) dan pakan komersil tanpa air rendaman jeroan ikan cakalang sebagai kontrol .
erlakuan A).
Data variabel penelitian terdiri dari laju pertumbuhan dan kepadatan populasi Daphnia sp.
menggunakan analisis ragam.
Hasil penelitian menunjukkan bahwa laju pertumbuhan populasi tertinggi pada perlakuan menggunakan air rendaman jeroan 4,5 ml/L dengan nilai 11,59% dan dengan kepadatan individu 260 individu/liter pada hari pemeliharaan ke 19.
Daphnia sp.
yang dihasilkan dari perendaman jeroan ikan cakalang juga dapat digunakan sebagai pakan alami untuk pertumbuhan dan perkembangan ikan Betta (Betta sp.
) walaupun efektivitasnya masih lebih rendah dibandingkan bahan organik lainnya.
Kata kunci: Daphnia sp.
, jeroan cakalang, kultur massal, pertumbuhan Indra Cahyono et al.
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INTRODUCTION Aquaculture of ornamental fish is one of the most economically profitable activities (Choi et , 2024.
Diatin et al.
, 2019.
Arfah et al.
, 2.
The selling value of ornamental fish is not only considered in terms of total size and/or weight but is more often based on each fish.
The value can reach even higher if it has a beautiful body shape and color (Saekhow et al.
, 2.
Based on information from the Ministry of Marine Affairs and Fisheries, the export value of Indonesian ornamental fish reached 39.
06 million United States dollars (US) throughout 2023.
The considerable market opportunity for ornamental fish is indeed really promising.
One of the ornamental fish that is profitable to be used as a business in aquaculture is the Betta fish (Betta sp.
) (Wiratama et al.
, 2.
This fish is relatively easy to cultivate but relies on natural feed to make its body shape more attractive and better movement (Sanjaya et al.
, 2.
Daphnia is one type of natural feed widely used in ornamental fish culture (Anshar et al.
, 2023.
Vasina et al.
, 2.
Daphnia sp.
is a zooplankton commonly used in freshwater fish hatcheries due to its high nutritional value (Hyman et al.
, 2021.
Rasdi et al.
, 2020.
Wiratama et al.
, 2.
The nutritional content of Daphnia sp.
depending on age and the food it eats.
Daphnia contains nutrients such as 4% protein, 0.
fat, and 0.
67% carbohydrates (Herawati et al.
Daphnia sp.
cultivation requires nutrients derived from suspended organic materials and bacteria from fertilizers added to the culture medium (Herman et al.
, 2.
Fertilization with organic materials is the optimal method to support the growth of the Daphnia sp.
population and enrich its nutrients.
In increasing the population of Daphnia sp.
, some studies use organic materials such as chicken and quail manure, tofu pulp and bran (Herawati et al.
, 2018.
Herawati et al.
, organic fertilizer (Abo-Taleb et al.
, 2.
and even wasterwater (Muir et al.
, 2.
Various organic materials for the production of Daphnia sp.
have been used to find the most effective but at a low cost and easy to find.
One of them is utilizing offal waste from the fisheries Fish offal waste is also easy to find by utilizing local traditional markets or by storing fish offal from fish auction sites (TPI).
Fish offal waste generally contains various nutrients, including N .
P .
, and K .
, which are components of organic fertilizers (Rosadi & Catharina, 2.
One fisheries industry waste that has the potential to be utilized as a source of organic material for growing Daphnia sp.
is skipjack fish (Katsuwonus pelami.
offal waste.
This type of waste needs to be utilized promptly due to its perishable nature.
addition, if it accumulates, it will have a negative impact on the land and water environment.
In general, the products processed from skipjack offal waste by the community are food ingredients such as shrimp paste and Bekasang (Shalahuddin et al.
, 2.
In addition, other processed products are non-food ingredients, such as a substitute for fish flour in the production process of fish and livestock feed (Raeesi et al.
However, the use of tuna offal waste as one of the natural organic materials to increase the population of Daphnia sp.
has never been done Therefore, this study aims to determine the impact of skipjack offal soaking water (K.
on Daphnia sp.
mass culture on the growth of Beta fish (Betta sp.
MATERIALS AND METHODS
This research was conducted from June to July 2021 at the Natural Feed Division Installation and Fish Hatchery of Bontomansi Fish Seed Center.
Gowa Regency.
South Sulawesi.
This research design uses a quantitative experimental approach with two test animals.
Daphnia sp.
and Betta sp.
Cultivation of Daphnia sp.
with skipjack offal Before being used for the Daphnia sp.
cultivation, skipjack offal waste was fermented with a composition of 1 kg of skipjack offal waste, 1 kg of brown sugar, 2 liters of coconut water, and added with 8 liters of rice water, which was put in a closed container for 14 days.
The result of fermentation of skipjack offal was added to the culture medium of Daphnia sp.
, which is done every day with concentration, treatment A .
ommercial feed without skipjack offal soaking wate.
as a control, treatment B .
5 ml/L), treatment C .
5 ml/L), treatment D .
5 ml/L).
These doses were repeated three times and the control treatment had a standard water density.
The water used is sterile with neutralized chlorine disinfectant with an average temperature of 28AC.
The doses used in this study were to prevent toxic properties that may arise and result in the death of Daphnia sp.
It is also the basic dose for Indra Cahyono et al.
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the use of Daphnia sp.
culture media as in some literature that uses other waste media for Daphnia culture media.
Sampling Density of Daphnia sp.
cultured with skipjack offal waste is done daily to stabilize the supply and growth of Daphnia sp.
Betta sp.
Daphnia sp.
population density The population density of Daphnia sp.
converted using the formula (Holy & Sari, 2.
Note:
= Total of Daphnia sp.
individuals in the culture medium .
ndividuals/lite.
= Average total amount of Daphnia sp.
from the repeated measurement .
ndividuals/lite.
= Culture media volume .
= Water sample culture media volume .
Rate of Daphnia sp.
population growth The population growth rate of Daphnia sp.
was calculated using the formula by Gazali et al.
Note:
= Rate of population growth (%) = IndividualAos total at the start of treatment .
= IndividualAos total at the peak of population .
= Rearing period .
Betta sp.
This study used 12 aquarium containers with a size of 100y45y75 cm3 that had been filled with 100 liters of water.
Each container was filled with 10 Betta sp.
The Daphnia sp.
stocking density per container was 20 individuals per day.
Betta aged 1 month were reared with two spot small aeration points and fed with 10 Daphnia sp.
morning and evening per container.
Feeding Daphnia sp.
as food for Betta sp.
was carried out for 29 days.
Replacing water was done every three days, as much as 30% with a siphon and putting water with the driping technique.
Betta sp.
Length growth The absolute length growth of fish was calculated using the formula from (Asiah et al.
Gazali et al.
, 2.
as follows:
Note:
= Growth in absolute length of Betta sp.
= The length of Betta sp.
at the last rearing period .
= The length of Betta sp.
at the start rearing period .
Weight Growth The absolute weight growth of fish is calculated as follows (Setyono et al.
, 2024.
Sinaga & Mukti.
Note:
= Growth in absolute weight of Betta sp.
= The weight of Betta sp.
at the last rearing period .
= The weight of Betta sp.
at the start rearing period .
Proximate analysis Proximate analysis will be conducted at the Nutrition and Chemistry Laboratory.
Pangkep State Agricultural Polytechnic.
Proximate analysis will be tested following the Indonesian National Standard (SNI) work procedure shown in Table 1.
Table 1.
Feed Proximate Analysis Work Procedure.
Parameter Test References Protein SNI 01-2354.
4:2006
Ash Content SNI 2354.
1:2010
Water Content SNI 2354.
2:2005
Fat Content SNI 2354.
2: 2010
NFE
*NFE: Nitrogen free extract.
SNI 01-4086-2006
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Data analysis Utilization of skipjack offal soaking water as liquid organic fertilizer for Daphnia sp.
growth was analyzed using analysis of variance (ANOVA).
Treatments that had a significant effect (P<0.
were continued with the W-TukeyAos real difference test to determine differences in the impact between treatments.
RESULTS AND DISCUSSION
Result Density and growth rate of Daphnia sp.
The population density of Daphnia sp.
various media rearing changed as the population These results show the duration of each stage in its growth cycle.
The average of Daphnia sp.
population density data from the results of 30 days of rearing can be seen in Figure According to Figure 1.
Treatment B .
5 ml/L) showed the highest peak amount of Daphnia sp.
on day 10, which was 260 individuals.
It indicates that treatment B, with fermented skipjack offal waste concentration of 4.
5 ml/L, provides optimal nutrition for the growth of Daphnia sp.
This result was followed by treatment A with 240 individuals and treatment C with 215 The optimal dose to increase Daphnia growth is unclear from these results.
Treatments B and C .
5 ml/L) were not significantly different from the control (Treatment A), although they had a maximum increase of 40 individuals on any specific day.
It shows that at a certain point, the population of Daphnia sp.
experienced optimal Meanwhile.
Treatment D .
5 ml/L) had the lowest peak number of individuals, only 40 individuals on the first day, and showed no significant increase thereafter.
These results show that the high concentration .
5 ml/L) may be toxic to Daphnia sp.
, inhibiting growth or causing The average value of the population growth rate of Daphnia sp.
can be seen in Figure 2.
Treatment B .
5 ml/L) had the highest growth rate .
per da.
with a small standard deviation (A0.
indicating consistent and optimal growth.
the other hand.
Treatment C .
5 ml/L) had a lower growth rate than the control .
22 vs.
61 per da.
, with a small standard deviation (A0.
These results indicate that this treatment was ineffective at increasing the Daphnia sp.
Treatment A .
had stable growth .
61 per da.
with moderate variability (A0.
Then, the results of Treatment D .
5 ml/L) did not support the growth of Daphnia sp.
at all .
per day with standard deviation = 0.
From these results, it can be confirmed that this dose is toxic or not very supportive of the survival of Daphnia sp.
because of the nutritional imbalance.
The study showed that between treatments A and B, there were significant differences, indicating that Daphnia sp.
grew better at 4.
5 ml/L than the control.
In contrast.
Treatment C showed that higher concentrations began to reduce the density of Daphnia sp.
Therefore.
Treatment C to D showed a tolerance limit before toxic effects ANOVA and W-Tukey test for growth rate comparation of Daphnia sp.
The ANOVA test results showed an F-statistic value of 26.
17 and a p-value of 1.
03y10^{-.
These results indicate a significant difference between the treatment groups .
<0.
Based on these results, it is Figure 1.
Density population of Daphnia sp.
in various treatments of skipjack (Katsuwonus pelamis L.
) offal soaking water.
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known that the fermentation treatment of skipjack offal waste significantly affects Daphnia sp.
The results of the W-Tukey test can bee seen in Figure 3.
These results showed no significant difference in the population growth rate in treatments A and B .
= 0.
These results indicate that both treatments have almost the same effect on Daphnia sp.
It was significantly different in treatment D .
5 ml/L) compared to all other treatments .
<0.
, where Daphnia growth was much lower.
This indicates that this treatment caused a significant negative effect due to toxicity.
Length and weight growth of Betta sp.
The results showed that Betta sp.
fed with Daphnia sp.
, which grew in skipjack offal soaking water during each treatment, experienced an increase in body length.
The average length growth of Betta sp.
can be seen in Figure 4.
addition, the weight of the Betta sp.
during the study also increased.
The average increase in Figure 2.
Growth rate of Daphnia sp.
population in various treatments of skipjack (Katsuwonus pelamis L.
) offal soaking water.
Figure 3.
W-Tukey test for growth rate comparison.
Figure 4.
Length growth of Betta sp.
fed with Daphnia sp.
treated with skipjack (Katsuwonus pelamis L.
) offal soaking water.
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Betta sp.
weight can be seen in Figure 5.
The standard deviation of length and weight growth can be seen in Figure 6.
Treatment B .
5 ml/L) produced the highest length .
83 gram.
, indicating the effectiveness of Daphnia sp.
with the addition of fermented skipjack fish waste at this dose.
On the other hand, treatment D .
5 ml/L) had the lowest growth .
94 gram.
and smallest standard deviation .
, indicating similar but poor growth.
This probably occurred due to the negative impact of concentrations that were too high.
Treatment C .
5 ml/L) was not significantly different from the control (A), indicating that this dose did not have a better growth effect than the control.
The largest variation was found in treatment B .
ml/L) .
tandard deviation = 1.
, indicating the presence of high and low-growth individuals in this group.
The smallest variation was found in treatment D .
5 ml/L) .
tandard deviation = .
, indicating a homogeneous but not optimal effect on length growth.
Treatment B .
5 ml/L) had the highest average weight .
247 gram.
, indicating that this dose likely provided the best growth with the highest standard deviation .
The weight of Betta sp.
in this group varied greatly compared to the other treatments.
In comparison, treatment D .
5 ml/L) had the lowest average weight .
with the lowest standard deviation .
These results indicate that the weight of Betta in this group is more consistent and similar.
These results also indicate that this dose may be too high, so it has a negative impact on Betta sp.
Treatments A .
and C .
5 ml/L) had almost the same weights .
829 grams and 823 gram.
, indicating that the 7.
5 ml/L dose did not have a more significant effect than the Figure 5.
Weight growth of Betta sp.
fed with Daphnia sp.
treated with skipjack (Katsuwonus pelamis L.
) offal soaking water.
Figure 6.
Standard deviation of weight and length growth of Daphnia sp.
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control (A).
The relatively low variation in data from treatment C .
indicates that this dose can also provide more stable results.
Proximate test of skipjack (Katsuwonus pelamis ) offal waste The results of the proximate test of skipjack offal waste can be seen in Table 2.
The protein content is 21.
In addition, other organic content is also contained in skipjack offal waste, which can also support the Daphnia sp.
Discussion Population densities and growth rates of Daphnia In this study, the average density of Daphnia can be seen in Figure 1.
In treatments A.
B, and C, the average density increased from the beginning of the feeding until day 19.
The highest increase in individuals was obtained in Treatment B, with a total of 260 individuals.
was followed by Treatment C with 240 individuals and Treatment A with 215 individuals.
The same result also occurs when considering the average value of the Daphnia sp.
The highest number of individuals was found in Treatments A.
B, and C proves that skipjack tuna offal waste can be used to increase the Daphnia sp.
population density.
It is due to organic materials needed for the growth of Daphnia sp.
that contains in skipjack tuna offal waste (Chakma et al.
, 2022.
Zainudin et al.
Organic materials contained in skipjack offal water such as enzymes and amino acids are formed due to bacterial fermentation.
The addition of coconut water and rice water as a growing medium provides sufficient nutrients to ensure that the process of fermentation and breakdown of organic matter takes place properly (Cahyono et al.
, 2021.
Safitri et al.
, 2023.
Suartini et al.
, 2.
The increased population growth of Daphnia in the study because of the skipjack tuna offal 35% of protein nutrients (Jeerakul et al.
, 2.
and it can support the Daphnia sp.
In addition, the utilization of skipjack tuna protein hydrolysate can provide antioxidant peptides that are useful as natural food additives in the formulation of nutritional products.
That is potentially increases the nutritional value of zooplankton feed such as Daphnia sp.
(Rachman et al.
, 2.
Otherwise, the results show that the dose of skipjack offal water with concentrations 5 ml/L (Treatment B) resulted in a decrease in the Daphnia sp.
The growth of Betta sp.
that consumed Daphnia sp.
from treatment D .
5 ml/L) grew the least.
This is because the concentration of Skipjack offal water is too high, causing unbalanced nutrition that leads to the death of Daphnia sp.
In terms of the highest total individuals in this study, a value of 260 individuals/liter was This amount is still below the Daphnia given vermicompost fertilizer, reaching 353 individuals/liter (Rasman et al.
, 2.
The total amount of Daphnia sp.
in this study was also much lower than in other studies that used African catfish farming waste to cultivate Daphnia sp.
reaching 2375 tails/liter (Darmawan, 2.
Thus, it can be said that the offal waste of skipjack can be used to accelerate the growth rate of Daphnia sp.
but is less effective in terms of performance.
This condition is possible because the organic matter content of skipjack offal waste is still insufficient compared to other organic materials.
Daphnia sp.
growth are strongly influenced by environmental quality, including nutrient availability, toxin levels, and other environmental The addition of media for the growth of Daphnia sp.
using fermented skipjack fish waste as much as 4.
5 ml/L is the best dose to support the growth of Daphnia sp.
However, when the dose is increased to 7.
5 ml/L, the growth rate of Daphnia decreases due to physiological disturbances, such as decreased food digestion efficiency, reproductive disorders, increased oxidative stress or toxicity of the cultivation environment (Schwarzenberger, 2.
Wibisono et al.
state that adding organic waste would increase the abundance of phytoplankton, which is very important for Daphnia sp.
Fish waste contains high levels of organic nutrients, which are beneficial for the growth of Daphnia (Alvian et al.
, 2.
Furthermore.
Turcihan et al.
state Daphnia sp.
growth and survivability are positively affected by nutrient availability, especially when fed with yeast, which increases reproduction, population density, and survival rates.
Different diets also affected specific nutrient components, highlighting the importance of nutrient-rich feed for optimal Daphnia sp.
In this study, it was also seen that Daphnia sp.
the peak of abundance on day 19 and the next day decreased in number until the 29th day of rearing.
This growth pattern is similar to that experienced by several studies that have been conducted, which experienced a peak increase in the abundance of Indra Cahyono et al.
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Daphnia sp.
and decreased afterward.
It occurs because the organic matter used as a source of nutrition has decreased due to the abundant number of organisms that will consume it.
In general, the growth phase of Daphnia sp.
forms the same population growth pattern and resembles a sigmoid curve consisting of lag phase, log phase .
, stationary phase, and death phase (Herawati et al.
, 2.
Darmawan .
states that the peak abundance of Daphnia with any culture media is on day 10 depending on the nutrients in the media.
Growth acceleration can be faster, but the peak is also between days 9 to 11.
After that, the growth of Daphnia sp.
decreased at the point of decline phase on days It is caused by water quality factors, metabolic residues, and overpopulation, which causes harvesting of Daphnia sp.
for feed, which is usually done at the peak abundance population.
The pattern of zooplankton growth, including Daphnia, is similar to that experienced by several studies that have been conducted.
The life cycle of plankton always increases at a particular point, which then decreases due to several factors such as environment, food availability, and life cycle.
As stated by Herawati et al.
, the growth phase of Daphnia sp.
generally patterns the same population growth.
It resembles a sigmoid curve consisting of a lag phase, log phase .
, stationary phase, and death phase.
This situation occurs because the amount of organic matter used as a source of nutrition has been reduced because of the abundance of organisms that will consume Length and weight growth of betta fish (Betta sp.
Based on Figures 4 and 5, it can be seen that all treatments increased in length and weight growth every week.
Treatment B was at the highest-level regarding body length and weight gain.
In the second week, treatment B showed a significant weight increase.
At the same time.
Treatments A and C also showed a significant weight increase, but not as significant as treatment B.
On the other hand, treatment D showed a decrease in length and weight growth after three weeks.
This studyAos results prove that adding Daphnia cultured with skipjack offal waste soaking water can increase the length and weight of the body of the Betta fish by increasing its appetite (Wibisono et al.
, 2.
Although treatment B had high length growth descriptively, its length value was not statistically different from treatments A and C.
In addition, treatment B had a value significantly different from treatment D.
The same thing also happened to the weight increase of the Betta sp.
Treatment B had the highest value, followed by treatments A.
C, and D.
In treatment B.
Daphnia sp.
produced more than others, thus increasing the value of the growth With the high growth rate of Daphnia sp.
the nutrients obtained by Betta sp.
are sufficient to support the increase in length and weight.
The abundance of Daphnia sp.
as a natural food is beneficial in the metabolism of Betta fish so that their nutritional needs are fulfilled (Matielo et al.
, 2.
Daphnia sp.
produced from water immersion of skipjack offal is obtained in large enough quantities and can be used in Betta sp.
This is because skipjack tuna offal has a relatively high organic matter content including protein, fat, fiber, and calcium (Yan et al.
, 2.
This is evident from the skipjack offal proximate test results in this study, which can be seen in Table 2.
Daphnia sp.
is a natural food often used to rearing Betta sp.
(Matielo et al.
, 2.
Several studies have found that Daphnia sp.
still far below other natural feeds in aquaculture, especially silkworms (Tubifex sp.
) (Asiah et al.
and mosquito larvae (Abo-Taleb et al.
Mejia-Mejia et al.
, 2.
Skipjack stomach waste is rich in protein, amino acids, and essential fatty acids, which can increase the availability of nutrients for bacteria or microorganisms in the culture medium.
These microorganisms can produce metabolites beneficial to Daphnia sp.
such as vitamin B12 and bioactive compounds.
Fermentation also breaks down complex proteins into simpler peptides and free amino acids, which can improve the Daphnia sp.
digestive efficiency.
The unsaturated fatty acid content in fish waste can improve feed quality and accelerate Daphnia reproduction, ultimately increasing population Nutrient imbalance and toxicity occur at higher concentrations in treatments C and D, where nitrogen content (NHCEA.
NOCC-) and fermentation-derived metabolite compounds can become too high, causing osmotic stress and toxicity to Daphnia sp.
These aquatic organisms are particularly sensitive to free ammonia, which is neurotoxic and can cause impaired osmoregulation as well as gill tissue damage, leading to mass mortality (Hochachka & Somero.
Fermented fish stomach waste can also contain organic nitrogen compounds like indole, skatole, and sulfide.
When these compounds are available in high concentrations, they can be toxic to aquatic organisms (Chowdhury et al.
, 2.
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CONCLUSION Giving water soaking skipjack offal waste (Katsuwonus pelami.
with a concentration of 5 ml/L is the optimal treatment for Daphnia sp.
The Daphnia sp.
produced from the offal waste soak skipjack fish can be used to be an alternative natural food for Betta sp.
and give an impact on its length and weight.
Further research can explore the effectiveness of using tuna offal waste to reproduce Daphnia sp.
as a more economical and sustainable diet for Betta sp.
addition, other parameters can also be tested, such as the survival growth rate (SGR) of Betta sp.
fed with Daphnia sp.
, which is reproduced with skipjack offal waste soaking water.
ACKNOWLEDGMENT
The authors would like to thank Institut Teknologi dan Bisnis Maritim Balik Diwa for facilitating this research.
The authors declare that there is no conflict of interest in this research.
REFERENCES