Kualitas warna ikan koi sangat dipengaruhi oleh kandungan nutrisi pakan, khususnya karotenoid sebagai prekursor pigmen. Maggot Black Soldier Fly (Hermetia illucens) berpotensi menjadi sumber karotenoid alami karena mampu mengakumulasi pigmen dari substrat pakannya. Sel kromatofor pada ikan menunjukkan respons berbeda terhadap variasi kandungan pigmen dan nutrisi, sehingga jenis media kultur maggot dapat memengaruhi intensitas warna ikan. Penelitian ini menggunakan Rancangan Acak Lengkap dengan empat perlakuan dan tiga ulangan: (A) maggot yang diberi pakan labu kuning, (B) buah naga, (C) pepaya, dan (D) kontrol. Hasil penelitian menunjukkan bahwa maggot yang dikultur menggunakan labu kuning memiliki kandungan karotenoid tertinggi (0,3269 mg/L), diikuti perlakuan pepaya dan buah naga. Perlakuan A juga memberikan peningkatan warna paling signifikan, dengan skor 25 pada skala TCF dan jumlah sel kromatofor tertinggi, yaitu 1.255 sel. Peningkatan jumlah sel kromatofor menyebabkan distribusi pigmen lebih merata sehingga menghasilkan warna koi yang lebih cerah. Seluruh perlakuan menunjukkan tingkat kelangsungan hidup 100% selama 30 hari pemeliharaan. Parameter kualitas air selama penelitian berada dalam kisaran optimal bagi kehidupan ikan koi. The nutritional content of koi fish's feed, particularly the carotenoids that serve as pigment precursors, greatly influences their color quality. Black soldier fly maggots (Hermetia illucens) have the potential to be a source of natural carotenoids because they are able to accumulate pigments from their feed substrate. Chromatophore cells in fish show different responses to variations in pigment and nutrient content, so the type of maggot culture medium can affect the intensity of fish color. This study used a completely randomized design with four treatments and three replicates: (A) maggots fed yellow pumpkin, (B) dragon fruit, (C) papaya, and (D) control. The results indicated that maggots cultured using pumpkin had the highest carotenoid content (0.3269 mg/L), followed by the papaya and dragon fruit treatments. Treatment A also provided the most significant color enhancement, with a score of 25 on the TCF scale and the highest number of chromatophore cells, namely 1,255 cells. The increase in the number of chromophore cells caused a more even distribution of pigments, resulting in brighter koi colors. All treatments showed a 100% survival rate during the 30-day maintenance period. Water quality parameters during the research were within the optimal range for koi fish life.