Fish frequently come into contact with water-borne pathogens. Fish are susceptible to several illnesses caused by macro and microorganisms. As a result of ectoparasite Trichodina's widespread early infestation, significant financial losses have occurred. Currently, it appears that formalin is worthless for treating ectoparasitic diseases in freshwater fish. Furthermore, formalin may leave hazardous residues in the fish flesh and the environment that are ultimately damaging to consumers. But this problem can also be resolved by using medicinal plants. The therapeutic herbs can work as immunostimulants, providing fish with activating non-specific defensive mechanisms and enhancing their specialized immune response. Indian almonds and garlic have been used to cure Trichodina sp. for an ectoparasite of tilapia fish.