Silvoaquaculture is one of environmentally friendly aquaculture, which is integration between fish ponds (brackish water aquaculture) and mangrove tree in the coastal area. In Indramayu Regency, silvo-aquacultures are located in Karangsong, Brondong and Tegur village. Milk fish (Chanos chanos) was cultured at silvo-aquaculture in Indramayu Regency. The objective of this study is to know water quality at silvo-aquaculture ponds in Indramayu Regency. The water quality has been measured includes temperature, salinity, pH, brightness, DO, nitrate, phosphate, and ammonia. The ranges of water quality values at silvo-aquaculture ponds in Indramayu Regency are Brondong Village {temperature (29.8-33.0 °C), salinity (26-30 ppt), pH (7.27-7.80), brightness (26.5-91 cm), DO (3.1-10.7 mgL−1), nitrates (12.5 mgL−1), phosphates (0.03 mgL−1), and ammonia (0.25 mgL−1)}; Karangsong Village {temperature (29.5-31.0 °C), salinity (17-25 ppt), pH (7.29-7.51), brightness (39.5-47 cm), DO (2.2-4.4 mgL−1), nitrates (12.5 mgL−1), phosphates (0.03 mgL−1), and ammonia (0.25 mgL−1)}; and Tegur Village {temperature (30.4-31.8 °C), salinity (15-19 ppt), pH (7.14-8.18), brightness (32.25-48.25 cm), DO (8.8-9.5 mgL−1), nitrates (12.5 mgL−1), phosphates (0.03 mgL−1), and ammonia (0.25 mgL−1)}. Analysis of variance showed temperature, pH, brightness, phosphate, nitrate, and ammonia were not significantly different between locations, but salinity and DO were significantly different between locations. These results indicate all water-quality parameters are suitable for fish culture. The lower salinity presented in Tegur Village was affected by rainy. Interestingly, DO concentrations in the Karangsong silvo-aquaculture pond are lower than optimal value (<5.00 mg/l), but they are still suitable for milkfish life (> 2 mg/l).

Research on extreme wave generation is one intensive research on water wave study because the fact that the occurrence of this wave in the ocean can cause serious damage to the ships and offshore structures. One method to be used to generate the wave is self-correcting. This method controls the signal on the wavemakers in a wave tank. Some studies also consider the nonlinear wave generation in a wave tank by using numerical approach. Study on wave generation is essential in the effectiveness and efficiency of offshore structure model testing before it can be operated in the ocean. Generally, there are two types of wavemakers implemented in the hydrodynamic laboratory, piston-type and flap-type. The flap-type is preferred to conduct a testing to a ship in deep water. Single flap wavemaker has been explained in many studies yet snake-type wavemaker (has more than one flap) is still a case needed to be examined. Hence, the formulation in controlling the wavemaker need to be precisely analyzed such that the given input can generate the desired wave in the space-limited wave tank. By applying the same analogy and methodhology as the previous study, this article represents multi-directional wave generation by implementing snake-type wavemakers.

The purpose of this community service activity is to transfer knowledge about the application and use of bioquaponic technology which is the integration of biofloc technology and hydroponic systems. The target of this community service activity is ornamental fish cultivators and the general public in Ciomas District, Bogor Regency. The activity was carried out in December 2021. The method of community service activities carried out was the lecture method, discussion and demonstration of direct practice in the field.  The results of this community service activity in Ciomas Subdistrict, Bogor Regency, show that there is a transfer of knowledge regarding the integration of bioaquaponics, biofloc technology, hydroponic systems, fish disease management, business development and group dynamics as well as demonstrations of the application and use of bioaquaponics. Based on the results of the pre-test and post-test conducted before and after community service, there was an increase in the capacity and capability of the representation of ornamental fish cultivators, which increased by 50 percent on average. The ornamental fish farming business actors who represent the cultivating community in this activity also get new networks to strengthen the collaboration of the ornamental fish cultivator community, business people and universities. Thus, the expected output of activities in community service in Ciomas District, Bogor Regency, namely (i) an increase in knowledge of ornamental fish farmers regarding the integration of aquaculture systems with biofloc technology and aquaponics systems, (ii) increasing the quality and quantity of ornamental fish production, and (iii) an increase in the network of ornamental fish cultivators in Ciomas District, Bogor Regency, can be achieved.

Silvoaquaculture is a model of brackish water ponds that combines aquaculture with mangrove conservation. This study examines aspects of feed conversion ratio (FCR) and survival rate (SR) as benchmarks for milkfish production that are maintained in three different types of silvoaquaculture ponds (Empang Parit, Komplangan, and Kao-kao Ponds). This research was conducted in Indramayu Residence (Indonesia). Data collected by questionnaires and determination of the respondents was done by purposive sampling with the aim of getting fish farmers in silvoaquaculture ponds. Data analysis uses a statistical test approach (ANOVA and DMRT). The milkfish that are cultivated in silvoaquaculture ponds have a survival rate ranging from 25.00%-80.00% with an average of 52.98%. Survival rate between types of silvoaquaculture ponds was different; Empang Parit ponds produce the lowest survival rate (average = 44.98%) and Kao-kao ponds have the highest survival rate (average = 59.64%). Mangroves become predatory animal habitats, so milkfish survival in silvoaquaculture ponds is low. The best feed conversion ratio of a Kao-kao pond is 1.63, followed by a Empang Parit of 1.82, and a Komplangan of 1.92. Feed conversion ratio between types of silvoaquaculture ponds was not significantly different. Mangrove ecosystems contribute to high nutrient waters, so natural food grows well and becomes additional feed for milkfish.