Improvement of Red Color Quality in Koi Fish ( Cyprinus carpio) Through the Addition of Rosella Extract in Feed ( Hibiscus sabdariffa)

Koi fish (Cyprinus carpio) is one of the ornamental fish that has a beautiful body shape and color, so it has high economic value. To get koi fish production with good color quality, several supporting factors are needed, one of which is feed. In this study, rosella (Hibiscus sabdariffa) extract was used as an additive in koi fish feed. The purpose of this study was to determine the effect of rosella extract on increasing the red color of koi fish through the addition of ingredients in the feed. The study was conducted using a completely randomized design with doses of rosella extract in the feed formulation as a source of anthocyanins, namely: 0% (control), 1%, 3%, 5%. Feeding was done three times a day with a feeding rate of 5%. Maintenance was carried out for 30 days and observations of color brightness of koi fish were carried out once a week using a modified TCF (Toca color finder). The results showed that the addition of rosella extract by 5% resulted in the highest value of red brightness every week. For water quality parameters, both temperature, pH, and dissolved oxygen are still within optimal limits for koi fish.