Availability of water in swamp areas is abandon almost throughout the year, therefore these areas are potential for aquaculture development. However, the characteristics of swamp water is mainly acid water, therefore, it becomes mayor problems in swamp fish culture development. Liming of ponds is intended to increase pH value of soil and water of fish ponds. A. granosa shells is one of domestic waste containing of 61.16% CaO and 21.65% MgO, therefore it can be used as an alternative material for liming of fish ponds. The aims of this research was to evaluate the potency of lime derived from A. granosa shells to raise soil's and water's pH, and to evaluate its effect to survival and growth of Pangasius sp. The research was conducted and arranged based upon completely randomized design with five treatments and three replications. The treatments used consisted of different dosages of lime, namely : P1) 1 ton/ha; P2) 2 ton/ha; P3) 3 ton/ha; P4) 4 ton/ha and P5) 5 ton/ha of lime equivalent to CaO. The results showed that both the soil and water reach a neutral pH at a dosage of 2 ton/ha (P2), 3 ton/ha (P3), 4 ton/ha and 5 ton/ha. The dosage of 5 ton/ha (P5) was the best treatments among all treatments, with a highest survival rate (100%), absolute growth of fish lenght (9.35 cm) and weight (40.69 g), as well as feed efficiency (110.97%).

ABSTRACT   Intermediate and holding rearing of botia face several problems such as the limited land, water quality, and decreased growth. The application of a recirculation culture system using the blood clam filter is increased to water quality and expected to solve the problems. This study aimed to analyze the production performance of botia fish on intermediate and holding rearing in the recirculation system by utilizing blood clams as the filter. This study used a factorial completely randomized design with two factors; clam particle sizes (1 mm, 2 mm, and 3 mm) and dosages (1.4 g/L, 1.8 g/L, and 2.2 g/L). Every experiment was conducted in three replication. The aquarium used in this study was 40×40×60 cm3. The size of fish samples was 3.5 ± 0.5 cm with the stocking density (3 fish/L, each test aquarium). The recirculation system was applied seven days before the fish were stocked. Every 15 days, weight and length of fish were measured (for 60 days). The results of physical (temperature) and chemical (pH, dissolved oxygen, ammonia dan nitrite) water quality in the recirculation system using the blood clam filter showed good conditions for botia fish. The stress response of botia blood glucose and TKO fluctuates with environmental changes. Mineral water and fish produced by calcium, magnesium, and phosphorus increase until the end of maintenance. There is an interaction at TKH between particle size and the dose of blood shells, whereas, LMPW, LMPL, and RKP significantly different only the use of dose 2.2 g/L.   Keywords:  Clamshells, botia fish, pH value, minerals, recirculation. ABSTRAK   Permasalahan pada proses penampungan ikan botia yaitu keterbatasan lahan, kualitas air yang buruk dan pertumbuhan ikan botia yang lambat. Penerapan sistem resirkulasi menggunakan cangkang darah dapat meningkatkan kualitas air dan kinerja produksi. Penelitian ini bertujuan menganalisis kinerja produksi budidaya ikan botia pada sistem resirkulasi dengan pemanfataan cangkang kerang darah sebagai bahan filter. Penelitian ini menggunakan rancangan acak lengkap faktorial dua faktor, yaitu ukuran partikel cangkang kerang darah (1 mm, 2 mm, dan 3 mm) dan dosis cangkang kerang darah (1.4g/L, 1.8g/L dan 2.2g/L). Setiap perlakuan dilakukan dengan tiga kali ulangan. Akuarium yang digunakan dalam penelitian berukuran 40×40×60 cm3. Ikan yang digunakan berukuran 3.5 ± 0.5 cm dengan padat tebar 3 ekor/L. Sistem resirkulasi dioperasikan selama tujuh hari sebelum ikan ditebar. Bobot dan panjang ikan diukur setiap 15 hari selama 60 hari pemeliharaan. Penelitian dalam sistem resirkulasi menggunakan cangkang kerang darah pada media filter menghasilkan kondisi kualitas air suhu, pH, oksigen terlarut, amonia dan nitrit air. Respons stres ikan berupa glukosa darah dan tingkat konsumsi oksigen (TKO) berfluktuasi seiring dengan perubahan lingkungan. Mineral air dan ikan yang dihasilkan meliputi kalsium, magnesium dan fosfos meningkat hingga akhir pemeliharaan. Parameter tingkat kelangsungan hidup (TKH) memiliki interaksi  antara ukuran partikel dan dosis cangkang kerang darah, sedangkan untuk laju pertumbuhan bobot mutlak (LPMB), laju pertumbuhan panjang mutlak (LPMP) dan rasio konversi pakan (RKP) berbeda nyata dengan penggunaan dosis 2.2 g/L.   Kata kunci:  Cangkang kerang darah, ikan botia, pH, mineral, resirkulasi.