Review : Ammonia adsorbent development for white-shrimp ponds

. Ammonia is a harmful organic substance for aquaculture existence coming from high-protein foods that significantly enhances the growth of white-shrimp. The cultivation rate of artificial feed production increases the water-soluble ammonia load. Unfortunately, not all regional regulations adopt the Minister of Environment Regulation to limit ammonia levels to no more than 5 mg/L. Adsorption is an alternative solution to remove or reduce ammonia levels in liquid waste bodies. This study aims to describe the efficiency of ammonia absorption as a form of environmental management towards sustainable coastal resources, especially in hatchery of vannamei ’ s. The points of the discussion are the technology used in the adsorbent pre-treatment strategy, laboratory scale, and field tests for the adsorption of water-soluble ammonia. Various types of adsorption materials were compared to determine the best physical and chemical properties to be used as biosorbent. Results of the review show that applying composite technology is able to absorb more ammonia compared to a single material. An important point are finding the right adsorption material and the number of times this material which can be used to adsorb ammonia material. this has an effect on the need for provision costs for waste management in the hatchery.


Introduction
One of the fisheries industries causing pollution, especially in the coastal environment, is shrimp farming in the region.This provision is clearly stated in UUPPLH-2009 that environmental pollution is the entry or inclusion of living things, substances, energy, and/or other components into the environment by human activities so that they exceed the established environmental quality standards.Susiana [1] states that shrimp farming activities in the Madayin area, Sambelia District, East Lombok show the habit of cultivators that ignore the preservation of coastal nature by disposing of the production and cultivation waste directly into the sea without being processed first.In addition to coastal areas, whiteshrimp can also be built in estuaries, which are natural meeting areas between fresh water and seawater (estuaries), directly impacting the supply of contaminants to river loads.[2] stated that the Kembung River in the Bengkalis Riau region would become increasingly turbid due to the disposal of waste in the form of leftover feed from White-Shrimp's production activities.In addition, the remaining products in the form of shrimp and plankton waste are organic matter in the form of suspended and dissolved solids, which are retained through the water flow and become a source of organic matter in the affected ponds [3].
Ammonia is one of the B3 organic wastes (toxic and dangerous materials) which is the focus of reduction for shrimp-pond farmers [4].This term is appropriate to use for ammonia waste because concentrations above 0.1 m/L will result in death of farmed animals (Ministry of Fisheries and Marine, no.37 in 2019).Apart from that, the ammonia content in fishery activity waste must not exceed 5 mg/L (Ministry of Environment and Forestry no.6 in 2007).Currently, programs from the government, especially from the Ministry of Environment and Forestry, have also tightened the requirement for sending samples of cultivation water and wastewater treatment plant to monitor waste content.When monitoring results for waste content show levels above the threshold, assistance and guidance will be provided in accordance with applicable regulations [5].For the environment too, the presence of high concentrations of ammonia will trigger eutrophication which causes a lack of dissolved oxygen and toxic conditions in the waters [6].Aquaculture activities, especially shrimp, generally require feed with high protein content.Farmers fill this need by using artificial feed which tends to produce feed stockpiles which trigger an increase in dissolved ammonia levels.Until now, the strategy used by farmers to reduce ammonia levels is to add high concentrations of chlorine, which actually increases the content of dangerous substances for the environment [7].Therefore, it is very important to find ways to reduce dissolved ammonia content, especially in fish farming activities.
Future-oriented industrial activities must prepare for integrated industrial processes, which means they must involve all sectors supporting long-term production sustainability.Nurhasni [8] explain that industries aiming to meet export needs must consolidate the elements of environmental management that reflect the level of industry players' concern for society and the environment in their production activities.Several domestic industries that have foreign business partners have required ISO 14001 certification as a condition for the exported products.Nevertheless, the industry with the ISO 14001 certification undoubtedly has a large enough capital to fulfill every environmental management quality standard.Meanwhile, people, especially in coastal areas and estuaries, who have ponds, individually and in groups, tend to have medium to significant capital and are still oriented towards fulfilling the life necessities.This review aims to obtain data on the effectiveness of these technologies and future follow-ups, especially in reducing the hazardous substance of ammonia.

Review method
One method that allows researchers to test theory-driven expectations directly against empirically derived groups or cells is contrast analysis.Despite its apparent advantages, contrast analysis is used even when a strong a priori hypothesis is available [9].Therefore, this review uses a contrast method approach which aims to find differences between several research journals that have been published, followed by concluding.The contrast method is one of the favorite review methods since it is helpful as a guide for obtaining the best materials and methods, and there is a gap for development to find new things for researchers [10].As a reference for review materials, the primary sources are from studies that have been published with the keywords "ammonia in aquaculture," "ammonia removal," and "adsorbent for ammonia."Fig. 2 shows the distribution of research that has been conducted basis on Google Scholar using the previously mentioned keywords, with a total of 1000 articles written from 2002 to 2021.The selection of Google Scholar may offer ease of access on global search sites without being limited to subscription capabilities so that everyone can read the article and use it both as a reference source and as a solution to problems, especially water problems due to ammonia.

Fig. 2.
The interrelationships of ammonia adsorption efforts as aquatic waste in the 2002 2021 range.
Fig. 2 explains that ammonia and ammonium are common problems, especially in water.Various studies have been carried out in terms of the effects of ammonia and ammonium, efforts to suppress concentrations, and how to carry out recovery for ecosystems affected by the accumulation of ammonia components.This review takes several of the latest journals to compare the benefits of adsorbing ammonia in aquatic environments.Through existing investigations, it is hoped that the best method that can be applied will appear, especially in the aquatic ecosystem environment of aquaculture.

Fishery waste quality standard system
Pond water management in white-shrimp cultivation activities, especially in East Java Province, uses high levels of chlorine powder.High chlorine levels in coastal areas will actually harm the lives of biota affected by wastewater managed with chlorine.Contrary to the concept of a sustainable fishery industry, wastewater management is something that cannot be taken for granted.Fishery waste management is still one of the challenges to realizing sustainable aquaculture productivity, as illustrated in Fig. 1.
The availability of fishery raw materials will always be sustainable if industry players can manage natural resources into sustainable raw materials.Regulations governing the quality standards of upstream fishery business waste need to be reformulated in regulations that specifically address the management of aquaculture waste, both fish and shrimp.concerning Wastewater Quality Standards must be a provision for all industries that dispose of their waste into the environment.This regulation combines a series of regulations related to wastewater quality standards.One source of these regulations is the Regulation of the State Minister for the Environment Number 06 of 2007 concerning Quality Standards for Industrial Wastewater Processing of Fishery Products.Fig. 2. Waterwaste management concept in aquaculture [11].
The analysis related to the environmental impact of the fishing business is finally brought closer to the existing regulations, namely regulations that process fishery products.Only in 2021, through the Regulation of the Minister of Maritime Affairs and Fisheries of the Republic of Indonesia Number 26 of 2021 concerning Pollution Prevention, Prevention of Damage, Rehabilitation, and Improvement of Fish Resources and the Environment, this Regional Regulation firmly states that a governor, mayor/regent head of the region, and everyone who carries out fish handling and/or processing activities related to all activities containing fishery commodities, is obliged to prevent Pollution of Fish Resources and the Environment.Waste quality standards, especially liquid waste generated from all fishery commodity management activities, must also meet the requirements for Wastewater Quality Standards following the provisions of the laws and regulations previously mentioned.
Both traditional, semi-intensive, and super-intensive cultivation generally carry out the Ammonia is a parameter that indicates the content of chemical substances with complex risks affecting not only the physics and chemistry of the waters but also the presence of biota, which tends to harm the welfare of fish and shrimp.Stated that aquaculture wastewater, especially in coastal areas, generally contains protein and fat, which results in a higher content of some organic matter, such as ammonia.These ingredients can stimulate the growth of microalgae such as Chlorella sp. to grow faster than normal, impacting competition for dissolved oxygen in the waste.[12] Explained that the higher the technology applied, especially in vannamei shrimp farming, the more protein-rich feed or pellets used in larger quantities than in traditional shrimp farming.The protein content in shrimp pellets is relatively high, around 40%, which can produce waste rich in organic N, including ammonia, a toxic compound for shrimp [9].
All forms of business or industry should follow the ISO-14001 Environmental Management System, in which all employees must play an active role in improving environmental quality and waste management.Solid waste can be in the form of residual catalysts, classified as B3 waste, and easily soluble when washed away by water which can contaminate soil and water.Liquid waste regulations follow the Decree of the Minister of the Environment No.  [13].
The regulation of the State Minister for the Environment related to the Quality Standards for Liquid Waste has been reduced to several regional regulations that regulate cultural businesses, especially shrimp, as a form of environmental concern to create sustainable fisheries commodities.Table 2 shows the limits for the maximum toxic level of ammonia that must be maintained in aquaculture effluents.
According businesses and/or healthcare facilities is 10 mg/L.Meanwhile, based on the State Ministry of the Environment Decree Number KEP-51/MENLH/10/1995, the ammonia quality standard threshold is 1 mg/L for group I and 5 mg/L for group II.The results of regulatory monitoring available in cyberspace show that not all provinces have regulated the appropriateness of the ammonia level specified in shrimp farming in Indonesia.For example, the Governor's Regulation Number 52 of 2014 about the quality standards for industrial wastewater, which is regulated for the maximum limit of contaminants discharged, does not mention the limitations of provisions in the aquaculture business or industry.Meanwhile, the number of aquaculture businesses in East Java Province, specifically shrimp farming, which achieved the highest production in the vannamei shrimp farming business was 3,784.55 tons per year with a production value of 232,611.01 million rupiahs (Central Agency for Fisheries Statistics of East Java Province, 2018).Therefore, this review concerns the research results of several relevant technologies to reduce ammonia levels in shrimp farming waste.Table 2. Wastewater Quality Standards for Ammonia in shrimp farming.Source: Regional Regulations and Governor Regulations.

Wastewater management using absorbent products
Using environmentally friendly technology can reduce the number of hazardous materials such as ammonia dissolved in water.One of the treatment techniques that can be used to treat wastewater is adsorption.Adsorption occurs due to the attractive force between the adsorbate molecules on the surface of the adsorbent.A substance can be used as an adsorbent for separation if it has a selective adsorption capacity, a large surface area per unit mass, and a strong affinity for the substance to be separated physically or chemically.These compounds will be adsorbed into the pores of the adsorbent surface.The adsorption process of a combination is influenced by several factors, including temperature and environmental pH, characteristics of the adsorbed elements, type and amount of adsorbent, and treatment during adsorption, such as contact time and stirring speed [14].Adsorption methods generally use activated carbon, chitosan, limestone, and quicklime to adsorb dissolved materials in wastewater, such as heavy metal content in wastewater and phenolic waste [15].The important thing in the adsorption process is selecting the type of adsorbent with high porosity and large surface area [16].Table 3 summarizes several studies related to the application of the adsorption process to reduce the ammonia content in liquid waste.Recent research states that some materials used as adsorbents can be applied in two methods to get the best adsorption efficiency values.These materials are roughly categorized into conventional (e.g., clay, carbonaceous materials) and nanostructured (e.g., MOFs) materials based on their structure and properties.Both have advantages and disadvantages.Bentonite, zeolite, other clay materials, and biochar remove NH 4 + from the water phase.In contrast, activated carbon and MOF remove NH 3 from the gas phase.Conventional materials are relatively abundant and low-cost, but their binding affinity for NH 3 /NH 4 + is usually weak.On the other hand, nanostructured materials can exhibit high adsorption capacity and fast adsorption kinetics in many cases.However, these materials are only prepared in the laboratory by tedious preparation procedures using expensive precursors.Hence the low yield and highly variable material properties.In this regard, modifying conventional materials to enhance their interaction with NH 3 /NH 4 + is a promising real-world application approach.

Province
The modification methods can be roughly divided into physical modification, including sonication, calcination (to increase surface area) and pelletization (to avoid pressure drop), and chemical modification (e.g., acid/base treatment, oxidation, and coating) to promote binding affinity.Following the order of adsorbent materials cost, here we first discuss abundant natural bentonite, zeolite, and other clay materials in their wild and modified form.The next is about biochar and activated carbon as biosorbents that need manufacturing but are potentially low-cost.At last, we briefly summarize novel materials still under laboratory testing, including MOFs and other nanostructured materials.
Table 3 shows several variations of adsorbents aimed at reducing ammonia levels in wastewater.Various treatments were applied to activate the surface, increasing the number of surface pores (high porosity) and increasing the surface area to absorb more ammonia.This strategy is generally carried out at the pre-treatment stage before being used as an ammonia-absorbing agent.The re-treatment steps can include selecting materials with more pores, treatment using high temperatures, modifying raw materials into composites, and giving several reagent solutions that provide ammonia-adsorbing ions [17].Dissolved ammonia is generally in the form of ammonium hydroxide, so in this case, the adsorbent ions are intended to adsorb the water-soluble ammonia.The illustration can be seen in Figure 5. Adsorption is the absorption of a substance on the surface of a solid.In the adsorption phenomenon, there is an attraction between the adsorbed substance and the adsorbent.In the adsorption system, the adsorbed phase in the solid is called the adsorbate, while the solid is the adsorbent.
The adsorption process can occur due to the unbalanced attraction of atoms or molecules on the solid surface that describe in Figure 5.With this force, solids attract other molecules in contact with the solid surface, either the gas phase or the solution phase, into the surface.As a result, the concentration of molecules on the surface becomes more significant than in the gas, solute, and solution phases [18].Fig. 3. Advantages and disadvantages for using conventional materials and nanostructured materials [19].Ref.

Bagas Flying Ash
Ammonia Waste from Tannery Adsorbent with a weight variation of 0.0; 0.5; 1.0; 1.5; 2.0 and 2.5 grams were stirred with a shaker, the adsorbent was soaked with a time variation of 0; 1; 2; 3; 4; and 5 hours at room temperature.The experiment was carried out at pH 7.0.

Ammoniawastewater
Pre-treatment in the form of washing using water (1:10) for 1 hour, at a temperature of 110oC.Followed by the addition of a layer of TiO 2 film along with 2 M NaOH with the help of HTAB surfactant into a composite.

79% [27]
Bentonit Domestic Ammonia Waste Activation of bentonite using 6% HCl for 2-4 hours with heating up to 1200 o C. Immersion of bentonite and ammonia was carried out for 30-120 minutes with stirring (20-100 rpm).

Adsorbent raw material activated carbon lignite
Activated charcoal, commonly referred to as activated carbon, is a type of black absorbent in the form of granules, rounds, pellets, or powders.Activated carbon is an amorphous compound produced from materials containing carbon or charcoal, which are especially treated to obtain high adsorption power.Activated carbon can adsorb certain gases, and chemical compounds or their adsorption properties are selective, depending on the size or volume of the pores and surface area.The absorption of activated carbon is extensive, 25-100% by weight of activated carbon [31].Ruhmawati, et al. [32] research by making a composite of activated carbon and plastic ore still needs to be more efficient in absorbing dissolved ammonia in hospital waste because it can only adsorb at a total efficiency of 50%.Some areas in Indonesia, such as Aceh, can utilize existing natural resources to produce activated charcoal.The use of coffee grounds as activated carbon [24] as a biosorbent can be done considering that the source of this biosorbent can be easily found in Aceh Province.Coffee drinks are one of the drinks that the people of Aceh quite like.Using activated charcoal from coffee grounds is relatively easy to reach in terms of raw materials and physical treatment.Using coffee grounds activated charcoal as an adsorbent for ammonia is also more efficient, around 66.6%, since it has a surface area of up to 22,368 m 2 /g.When activated charcoal is applied to the fishing industry, especially in wastewater treatment, it becomes the most accessible material.Moreover, It has more economic value because the raw materials are easily found.To conclude, coffee grounds activated charcoal has a decent surface area to be used as an absorbent and is a good absorbent material.

Fly ash
Fly ash is the result of combustion in a boiler.One of the fly ash that can be used as an adsorbent is bagasse fly ash.Bagasse fly ash is sugar industry waste produced from burning bagasse.This waste is abundant and of no value to the sugar factory.If you use bagasse fly ash, only transportation costs are needed.Many researchers have used bagasse fly ash as an adsorbent for various pollutants from liquid waste, including metals [33][34], organic [35]- [37], and COD [38].But unfortunately, the efficiency of the adsorbent on ammonia removal using bagasse fly ash is only around 45.72% [21].Slamet and Imas [27] research tried to increase the efficiency of ammonia adsorption by utilizing fly ash composites with TiO 2 , which resulted in an increase in the sorption efficiency of dissolved ammonia to 79% but with a note that the conditioning when adsorption was carried out had to be at pH 12.

Bentonite
Bentonite absorbs Chromium metal in wastewater.Ding et al. [39] stated that bentonite could repel zinc cations, Cu (II) and Mercury (II), as well as other studies using bentonite and proven to be able to absorb metal relatively highly because bentonite has a reasonably sizeable external porosity and can expand when in water [40].Although bentonite clay is beneficial for adsorption, its adsorption capacity is limited.This weakness is overcome through the activation process using acids (HCl, H 2 SO 4 , and HNO 3 ).

Zeolit
Zeolites consist of hydrated aluminosilicate crystals containing alkaline or alkaline earth cations in their three-dimensional framework.The metal ions can be replaced by cations again without destroying the structure of the Zeolite, which can absorb water reversibly.Zeolites have a hollow structure; usually, these cavities are filled with water and exchangeable cations and have a particular pore size.Therefore, zeolites can be used as adsorbents, molecular filters, catalysts, and ion exchangers.One of the uses of Zeolite is for water management.The water in question comes from groundwater, distilled water, industrial waste, household waste, and agricultural waste.This dirty water contains insoluble waste, dissolved materials, and colloids.So dirty water must be handled mechanically, chemically, and biologically depending on the dirt and contaminants and the standard of clean water required.So along with the rate of weight gain of Zeolite, there is a decrease in Ammonia levels.The more Zeolite was added, the lower the ammonia pollutant level.The effectiveness of the use of this Zeolite is relatively high, reaching 58.34% [23].Research by Mayasari et al. [28] tried to combine bentonite and Zeolite with being used as an adsorbent which showed extraordinary results, with an efficiency of up to 92.89% to be able to absorb water-soluble ammonia.The layered nature of bentonite is filled with zeolite minerals in each layer to form a surface area to absorb more.

Biomass
The use of biomass products such as rice husks and sawdust have also been shown to be capable of being used as adsorbents to remove water-soluble ammonia, and it is proven that the adsorption efficiency for ammonia can reach 75.69% [26] and 96.34% [29].However, these two raw materials need to be activated first to further increase adsorption efficiency.In the activation process, impurities attached to the surface of the adsorbent can be removed to produce more pore gaps so that the adsorption surface area of the material becomes wider.Notes for the use of biomass in the pollutant adsorption process, namely when the amount of rice husk biomass is given too much during adsorption, there will be a competitive process for adsorption of substances other than ammonia which has sufficient affinity for rice husks.The process causes rice husk absorption as an adsorbent to decrease from the optimum state.

High temperature treatment
High-temperature treatment is one of the physical factors implemented on an adsorbent to form carbine through the carbonization process.The temperature used is in the range of 800 -1000 o C [14].Aman et al. [24] research using coffee grounds only requires a temperature of 400 o C for 3.5 hours for the calcination treatment.Some materials with layered characteristics, such as bentonite, require temperatures up to 1200 o C so that the layer can expand, have interchangeable carbons, and increase porosity [13].The higher the activation temperature, the more active the carbon produced, so it has a high absorption ability [41].However, [40] stated that applying high-temperature treatment alone is insufficient to make some adsorbents more efficient in absorbing their purpose in the adsorption of solutes.Adding additional activators, such as soaking with solvents, is necessary to increase surface activity.

Adsorbent composite modification
One method that has the potential to simultaneously overcome the problem of fly ash waste and ammonia liquid waste is to modify several types of industrial by-products as adsorbents for liquid ammonia waste.For example, fly ash can absorb ammonia with several factors that affect the adsorption capacity of fly ash, namely the ratio of SiO 2 to Al 2 O 3 , carbon residue, water vapor content and volatile compounds, and coal combustion temperature.It should be noted that adsorption technology has a weakness in that it cannot degrade waste into safer compounds but only transfers waste to the surface of the adsorbent and needs to be regenerated so that the adsorbent can be reused.Several studies such as fly ash/TiO 2 composites can be used as a medium for the degradation of methylene blue, surfactant dodecylbenzene-sulfonate-SDBS, and Cu 2+ [42] , Escherichia coli [43]), and Bemacid Red by 93%., and also Bemacid Blue by 77% for 240 minutes [44].
Unfortunately, this composite is less efficient to use as an ammonia adsorbent because it can remove ammonia up to 50%.The increase in hydroxysolidate in fly ash does not always positively affect fly ash as a side effect of administering SiO 2 and Al 2 O 3 .Watanabe et al. [9] provide a solution that the adsorbent is likely to be more efficient in absorbing ammonium hydroxide as a water-soluble form of ammonia if the ratio of SiO 2 and Al 2 O 3 is less.

Solvent as adsorbent activator
Several research results state that pre-treatment greatly determines the efficiency of ammonia entrapment in wastewater.This activation process requires a variety of trials of raw materials, which are given reagents in the form of specific chemical solutions to provide additional functional groups that can actively help absorb pollutants.Table 4 shows the effect of acids-bases on the adsorbent in absorbing ammonia.Some adsorbent raw materials require additional solvents to improve the adsorption performance further.According to the research of Papiounnaou [45] mesoporous silica material can be produced from the polymerization condensation process with fly ash precursor and has similar results to the results obtained from pure silica or tetraethyl orthosilicate (TEOS) sources.In addition, the surfactant's long chain will increase the , 06002 (2024) BIO Web of Conferences https://doi.org/10.1051/bioconf/2024900600290 ICGAB 2023 adsorbent material's pore size.However, for the preparation of this material, there needs to be a feasibility study considering that the cost required is quite significant, considering that the adsorbent raw material needs to be made in a composite manner, and it is still necessary to add additional chemicals to be able to activate the adsorbent.
Environmental pH needs to be considered in the ammonia adsorption process.Ammonia exists in water in two forms, ammonium ion (NH 4 + ) and non-ammonium ion (NH 3 ).The balance of ammonium in solution is strongly influenced by pH [46], and its ionic form can remove ammonium from the solution through ion exchange.Most ammonium exists in its ionic form at pH 8 and below.Therefore, it is possible to assume that these conditions favor the rapid removal of ammonium ions towards ammonium in its non-ionic form (NH 3 ).However, an increase in pH is unfavorable for the ammonium removal process.Several studies have shown that at a pH below 8 there is an increase in the number of hydrogen ions in the solution, thus providing a sufficient cavity for ion exchange competition.The behavior of ammonia in solution is at pH 5 to 7 in the form of ammonium ions (NH 4 + ) the main species that can exchange ions with cations in the zeolite.So under these conditions, the efficiency of ammonium removal is high.However, at pH above 10 where NH 3 is the predominant species, the efficiency of ammonium removal is low due to the lack of ion exchange capability in the primary form of NH 3 .120 min [24] HCl 6% 60 min [13] H 2 SO 4 Activates the adsorbent surface to adsorb ammonia.In the combination of bentonite and zeolite, H 2 SO 4 was used to activate the surface with an incubation time of 2 hours.
90 min [28] Base Solution Nessler Solution (K 2 HgI 4 ) In a strong base arrangement with nitrogen ammonia (N-NH 3 ) present in water, it forms a yellow-brown color group which is proportional to the level of ammonia and is compared with the standard color of ammonia and is examined with a spectrophotometer at the maximum wavelength absorbed by the standard solution which has a high concentration, namely at a wavelength of 480 nm.

min [23]
NaOH 2 M Activating the surface of the adsorbent which is also added with the addition of HTAB surfactant.HTAB surfactant acts as a promoter of the bond between fell ash and TiO 2 .The use of this HTAB surfactant helps the formation of mesoporous silica (MCM) materials, with fly ash as silica precursor.

Future work
Various studies of adsorbents in terms of ammonia adsorption have been carried out, starting from the use of minerals, by-products of coal production or the sugar industry, composite treatment, and variations in both physical and chemical treatments to conditioning when ammonia adsorption is carried out.Things that need to be considered in selecting adsorbents in environmental management, especially the removal of water-soluble ammonia, lies in the availability of adsorbent raw materials, additional costs for ammonia waste management the availability of labor in the treatment of each adsorption treatment.
Most of the studies have not covered scale-up and commercialization.Thus, an opportunity is widely open for further research, mainly for the Agroindustrial Technology cluster, to prepare the proper formulation for applying adsorbents to remove ammonia in white-shrimp cultivation in Indonesia.
The main principle in developing adsorbents to reduce ammonia content to manage the environment was developed from the ideas of [47].To make a product that has superior performance, as in this case is the development of adsorbent products for the preservation of coastal water resources, it is necessary to have an in-depth study of the basic philosophy of why environmental management is needed.This philosophy can be in the form of regulations that apply and are universally acknowledged, especially in ecological management, such as Good Agriculture Practices, Quality Control Management, and Quality Assurance for waste management.This philosophy is the basis for making laws, and regional regulations contain regulations regarding the maximum permissible limit for ammonia.However, until now, there has been no regulation underlying the maximum limit for ammonia in coastal areas.A workable solution is to implement existing rules with maximum ammonia levels in fresh waters temporarily applied to marine waters.Fig. 6.Eco-friendly adsorbent product orientation in supporting environmental management efforts [48].

Conclusion
Given the limited number of strategies for reducing ammonia, especially in shrimp farming, further review is needed on the: 1. Management of ammonia content which is part of toxic and dangerous waste from fish farming activities, especially shrimp ponds through the use of artificial feed must be an environmental issue that must be resolved by the relevant parties.carried out, both through conventional technology involving local wisdom raw materials and nano-level technology.However, this all needs to be reviewed, considering that high technology also requires quite high costs.3. Exploration of improving the quality of adsorbents has become a priority for efforts to increase adsorption capacity.The thing that needs to be considered is the physicochemical characteristics of the pores on the surface, because not all materials have a surface that is ready to absorb.4. Adsorbent applications also need to pay attention to the farmer's ability to procure goods, and the effects on the environment.
122 of 2004 concerning Amendments to the Decree of the State Minister of the Environment No. Kep.51/MENLH/10/1995 concerning Quality Standards of Liquid Waste for Industrial Activities.COD, TSS, Oils and Fats, NH 3 -N, TKN, pH, Discharge.The Quality Standard Value based on the Ministerial Decree is based on the pollution load, while the maximum wastewater discharge is 15 m 3 per ton of product.Quality Standards for Industry in the Province of South Sumatra Governor Regulation No. 8 of 2012 are the same as Kep.Minister of Environment No. 122 of 2004 standards

2 .
Several research efforts to obtain strategies to reduce ammonia content have been , 06002 (2024) BIO Web of Conferences https://doi.org/10.1051/bioconf/2024900600290 ICGAB 2023 Regulation of the Minister of Environment of the Republic of Indonesia Number 5 of 2014

Table 1 .
Centralized waste management has also been regulated in regulations issued by the government, more precisely in the appendix of Wastewater Quality Standards for Fisheries Industrial Areas Conducting Centralized Wastewater Treatment, in the Regulation of the State Minister Number 06 of 2007 concerning Wastewater Quality Standards for Industry, which are listed in Table 1.Liquid waste quality standards.Attachment to the Regulation of the State Minister of the Environment Number 06 of 2007 to the Minister of the Environment of the Republic of Indonesia Regulation Number 5 of 2014 concerning Wastewater Quality Standards, the ammonia level for

Table 3 .
Research that includes the application of the adsorption process to suppress the ammonia content in liquid waste.

Table 4 .
The effect of acid-base on the efficiency of the adsorbent to absorb ammonia.