Contributions of the periphyton to the growth of Nile tilapia (Oreochromis niloticus) fingerlings on different fixation substrates: an ecological approach

Abstract

Knowing about the ecological aspects involved in the commercial breeding of aquatic organisms becomes an important tool to make aquaculture more productive and less impactful. Thus, periphyton taxon composition and biomass on different substrates and the influence of these on water quality and growth parameters of Nile tilapia fingerlings were examined. An experiment with three treatments (substrates for growth of periphyton: geomembrane, polyethylene terephthalate (PET), and bamboo) and a control (without substrate), each with five replicates, was conducted in a greenhouse with controlled aeration and temperature. Each mesocosm was populated with ten tilapia fingerlings with an average weight of 2.3 g for 30 days. Water quality parameters were not significantly different among treatments but remained within that established by the environmental legislation. In all treatments, 36 periphyton taxa were observed. The bamboo substrate was the most diverse, which could be attributed to the fact it was a natural substrate. Regarding fish growth, there was a significant difference among the treatments, with the PET treatment having a higher condition factor (kn). The bamboo substrate was good for colonization concerning alga diversity; however, fish in the PET treatment and control exhibited higher performance and algae consumption values, respectively.

Keywords

• periphytic algae; ecologic aquaculture; commercial fish feeding