A Degassing Inlet Structure for Aquaculture Ponds

Abstract

Structures separating fish hatchery ponds from open spring water sources must restrict fish movement from the pond to the spring, allow for constant water flow, and potentially reduce incoming spring water gas supersaturation. This article describes a novel inlet structure that fulfills those requirements. In addition, it requires minimal maintenance, and allows for the quick and easy removal of debris in the event of partial plugging. This simple aluminum structure consists of a mount for attachment to the inflow pipe and a terminal splash plate with aeration holes. The splash plate is perpendicular to the water flow during normal operations to both prevent fish from jumping into the pipe and aerate the incoming water. However, it can be easily swiveled upward for the efficient removal of debris. Use of the inlet structure consistently decreased gas supersaturation in the spring water as it entered the fish production pond. By decreasing gas levels and maintaining water flows, potentially hazardous fish health issues can be avoided by using this structure. In addition, this relatively inexpensive and simple device will greatly reduce the labor required for removing debris compared to traditional screens.

Nitrogen Gas Saturation in Karst Springs Varies Throughout the Day

“…Nitrogen supersaturation in springs is of particular interest because of its well-documented negative effects on fish [8] [9] [10] [11] [12]. Aeration and degassing structures are used to reduce nitrogen gas levels and increase dissolved oxygen levels in spring water at McNenny Hatchery [13] [14]. Although nitrogen saturation is decreased with these structures, it still persists.…”