Low pH as the Limiting Factor for Survival of the Mosquito Larvivorous Fish, Poecilia reticulatus, in Impounded Sugar Mill Wastewater

Date
1986-03
Authors
Toyama, Gary M.
Journal Title
Journal ISSN
Volume Title
Publisher
Hawaiian Entomological Society
Abstract
Acidity below pH 5.5 caused asphyxiation of P. reticulatus despite adequate dissolved oxygen and low levels of carbon dioxide in sugar mill wastewater. Clogging of gills with precipitated iron when acidity fell below pH 5.5 is suspected of causing asphyxiation. No fish survived below pH 4.8 even at high DO and low CO2 levels. Survival of60% occurred between pH 4.9-5.3, while all fish survived above pH 5.5 even at low DO (0.3 ppm) and high CO2 (250 ppm) levels. Primary cause of low pH and high CO; levels was biological decomposition of suspended microscopic particles of sugar cane stalks. Major source of this material is from sludge precipitated by lime during clarification of cane juice. Separation of this sludge may increase pH in impounded wastewater to tolerable levels for fish survival.
Description
Keywords
Citation
Toyama GM. 1986. Low pH as the limiting factor for survival of the mosquito larvivorous fish, Poecilia reticulatus, in impounded sugar mill wastewater. Proc Hawaiian Entomol Soc 26:115-120.
Rights
Access Rights
Email libraryada-l@lists.hawaii.edu if you need this content in ADA-compliant format.