producers held an audition for the role of Prahlada, inviting many children in and around Madras (now Chennai) to AVM Studios. Roja Ramani was cast as Prahlada after a screen test and a song rehearsal in which she held a live snake. She was recommended to Meiyappan by her father Satyam's employer, an editor of the now-defunct magazine Cinema Rangam in Madras. Since Ramani was pale and thin, the producers approached a nutritionist to help her meet the role's requirements. Singer M. Balamuralikrishna was cast as the sage Narada, making his acting debut in film. When his choice was criticised (because of Balamuralikrishna's height), Meiyappan retorted that the casting was apt since the role would be used for comic effect. Haranath played the role of Vishnu. Relangi and Padmanabham were cast as Prahlada's teachers, Chanda and Amarka. Ramana Reddy and T. Kanakam were signed as snake charmers for a key scene. L. Vijayalakshmi played the royal dancer in Hiranyakashipu's court; Shanta, Vijaya Lalitha, Gitanjali, and Vennira Aadai Nirmala were cast as the apsaras (celestial dancers) Rambha, Urvashi, Menaka and Tilottama, respectively. Filming Bhaktha Prahlada was shot in Eastman Color Negative film, and was AVM's second colour film, after Anbe Vaa (1966). Although the script was completed by May 1965, the principal photography and post-production phases lasted for one-and-a-half years. Meiyappan produced another Telugu film, Ave Kallu (a remake of his 1967 Tamil production Athey Kangal), simultaneously with Bhaktha Prahlada. His sons were more interested in Ave Kallu than Bhaktha Prahlada, uncertain of the latter's commercial viability. When Sekhar showed the set designs to Meiyappan and his sons before building them, they rejected them in favour of Ave Kallu. Filming was delayed, and the cast and crew became impatient and frustrated towards the end of production. During filming, Ramani was trained by "Rangoon" Ramarao (who played Amarka in the 1942 film) in dialogue diction. In the scene where the snake charmers place a snake on Prahlada's shoulders, a trained wheat-coloured snake was used during rehearsals and a black cobra was chosen for the filming. For the scene where elephants are forced to trample Prahlada, a child stunt artiste from the Great Oriental Circus was initially engaged as Ramani's double. The child was dismissed when Ramani began crying, however, and she performed the scene herself. Balamuralikrishna remembered filming a scene as Narada: "I had to stand on a stool without proper balancing,