Estuarine Ariopsis bonillai, is considered in pe- ril of extinction. In spite of this, its capture in the Cienaga Grande de Santa Marta (CGSM) is very significant. Therefore it is important to learn more about its life history and to study the possibility of its use in culture. Initially, a technique to obtain estuarine “Bighead catfish fingerlings with incubating males was de- veloped. Later, pre-rearing assays were made in lm3 cages with a mesh size of 8mm. Triais included four stocking densities: 40, 80, 120, and 160 fishes/m3. Food, consisting in minced fish, 10% of the body weig- ht, was supplied daily Best results were obtained with the density of 40 fishes/m3, starting with a mean body weight of l,8g and finishing with an average of 45g after six months. Daily measurements of temperature and salinity were performed. In addition, dissolved oxy- gen was measured every month. High salinity variatio- ns were observed. During the rainy season a troubleso- me phenomenon in the Cienaga was caused by turbid and polluted waters proceeding from the Sierra Mevada de Santa Marta; all this originates perturbations in the water's physical-chemical conditions, bringing along fish deaths in the Cienaga, affecting also this experi- ment. Significant mortalities and relatively low weight gain were recorded, mainly at high stocking densities. This work was carried out in the Aquaculture Station of the Magdalena Gniversity at Palmira, CGSM.