AQUACULTURE, SEMARANG – Catfish is one of the most widely cultivated fishery commodities in Indonesia. The demand for catfish continues to increase every year, many people like it with its distinctive meat taste. The catfish market opportunity was caught by a catfish farmer in Mayong, Jepara. However, from some facts found in the field, catfish breeders in Mayong do not yet know how to produce seeds properly, so the resulting seeds are of poor quality and have a high mortality rate.

Aquaculture Study Program, Faculty of Fisheries and Marine Sciences (FPIK) Diponegoro University (UNDIP) tries to help the problems mentioned above through community service activities by a team led by Mr. Seto Windarto, sourced from the 2021 FPIK UNDIP Community Service Grant funds. dedication includes:

  1. Identification of resource performance and water quality management problems in the catfish hatchery business in Mitra.
  2. Formulation of appropriate technology in the management of catfish hatchery media water for Partners.
  3. Counseling to Partners.
  4. Monitoring and Evaluation of the results of outreach activities to Partners The method of implementing the service is carried out in an observative-participatory-solutional manner.

The service activity was carried out in March-June 2021 with partners, namely Pokdakan Catfish Cultivation Pond in Mayong Lor Village, Mayong District, Jepara Regency which still uses traditional cultivation systems. This causes the quality of the aquaculture media used by partners to be low due to the accumulation of dirt and residual feed that settles and causes disturbances in growth, appetite and causes death. The use of a simple filter in reducing physical and chemical residues from aquaculture waste organic material is expected to improve water quality on 3 (three) basic parameters, including: dissolved oxygen, pH and water ammonia levels.

The use of this filter is at the same time able to streamline the use of cultivation media water – considering the limited water sources – by reusing water (recirculation). The filtration system introduced to partners includes 3 (three) layers of filtration, including: (1) Physical filter, in the form of a sponge or dacron to filter dirt with large particle sizes such as feed residue, faeces and dust; (2) the first chemical filter, in the form of activated charcoal or zeolite to bind the remaining toxic metabolites in the water; and (3) a second chemical filter, in the form of bioball, gravel or coarse sand which functions to convert toxic nitrogen compounds into non-toxic compounds. After using for approximately 1 (one) cycle of seed production or 1 (one) month, the use of this simple filter can improve water quality, namely: Dissolved oxygen in water to > 4.8 mg/L; pH: 6.8 – 7.2; and ammonia levels <0.2 mg/L. The three water quality parameters showed a value that was quite optimal for catfish hatchery. Currently, the mentoring process for partners is still being carried out to see an increase in the survival of catfish seeds using this simple filter system. (admin)