Feasibility of improving water quality using Terminalia arjuna, Cinnamomum zeylanicum, and Azadirachta indica Leaf powder packs in Poecilia reticulata rearing tanks

Abstract

The inclusion of herbals into the aquatic media is extensively practiced by farmers, especially in ornamental fish farming, to enhance fish performance. A six-week experiment was designed to test the effect of Terminalia arjuna (TA), Cinnamomum zeylanicum (CZ), and Azadirachta indica (AI) leaf powders on water quality and growth performance of guppy fish (Poecilia reticulata). Dry leaf powder (3.0 g) was packed in a cloth bag and kept in the tank during the experimental period except in the control treatment (CT). Each treatment had three replicates and 12 fingerlings of P. reticulata (2.26 ± 0.03 cm; 0.12 ± 0.01 g) were introduced into each tank (56 L). In CT, water was daily siphoned, and 1/3 of the water was replaced at three-day intervals, but no water was replaced in other treatments. All the treatments were aerated continuously. Growth, feed utilization, and water quality parameters were monitored during the study. The final body length, weight, average daily growth, % weight gain, and specific growth rate in TA and CZ were significantly higher than those in CT and AI. The water quality parameters (pH, Phosphate, Ca2+ Hardness, conductivity, and total dissolved solids) in all treatments remained within acceptable ranges throughout the study. However, in AI treatment, ammonia and nitrite levels of water quality were elevated. After the eighth day, the ammonia levels in CZ and TA treatments decreased and it was lower for about 18 to 20 days and then started to increase until the end of the experiment. The final results showed that the growth, feed utilization, and water quality parameters of fish in CT, TA, and CZ were better than those of fish in AI. The survival rate of fish is good in all treatments. As water was not replaced in TA and CZ tanks, it will be helpful to reduce the cost of water as well as labor cost. Among the tested leaf powders, TA, and CZ leaf powders were better than AI leaf powder.