Chilton, E. W., 1991, System for maintaining sediment suspensions during larval
fish studies: Progressive Fish-Culturist, v. 53, no. 1, p. 28-33.

Abstract

A new system was developed for maintaining suspensions of inorganic solids
during laboratory studies on early life stages of fish. Microfine bentonite was
successfully held in suspension in specially constructed units during a 21-d fishless
test, a 28-d experiment with juvenile green sunfish (lepomis cyanellus), and four
shorter experiments (5-9 d) with four species of larval fishes, white sucker
(catostomus commersoni), northern pike (esox lucius), channel catfish (ictalurus
punctatus), and walleye (stizostedion vitreum). Each experiment on larval fish was
conducted until the yolk-sac had been absorbed. Concentrations of bentonite ranged
from 0 to 728 mg/l. Each unit consisted of a holding chamber set in a stainless steel
bowl and two submersible pumps that recirculated the suspension. Turbidity
readings remained nearly constant throughout each experiment. Because the
turbidity of suspensions was well correlated with bentonite concentration (r2 =
0.989) And easy to measure, turbidity was used as an indicator of concentration.
The system is inexpensive, easy to assemble, and does not require a diluter system
to maintain constant concentrations of suspended material.

Keywords