The effect of adding red dragon fruit peel extract (Hylocereus polyrhizus) in feed to increase color brightness in guppy fish (Poecilia reticulata)Siti Maulida, Nur Rahmah Harahap and Luvi Syafrida HandayaniBIO Web Conf., 156 (2025) 03016DOI: https://doi.org/10.1051/bioconf/202515603016