Larval killifish (F. heteroclitus) were produced from an in-
house culture of wild caught specimens (St. Augustine, FL).
Adult killifish were maintained in flow-through SW at ambi-
ent temperature and were fed ad libitum commercially available
dry pellet food. Groups consisting of one male and three to four
females were placed in separate tanks. For spawning, tanks were
fittedwith egg laying substrates overnight. Egg laying substrates
consisted of short (2 cm) lengths of PVC tubing covered with
fine plastic mesh in the bottom and a wider plastic mesh on the
top. Thewider plasticmesh on the top of the PVCtubing allowed
for eggs to fall through and collect on the fine mesh in the bot-
tom while preventing the adults from having access to the eggs.
Each morning eggs were removed from the spawning tanks,
rinsed briefly in de-ionizedwater andwere placed onmoist (FW)
papers towels in plastic petri-dishes. The covered petri-dishes
were placed in an environmental chamber at 25 ◦C and fungus
infected eggs and unfertilized eggs were removed daily. At day
14 post-fertilization, eggs were placed in 1 l Tripour® plastic
beakers containing 0.8 l of water at the planned test salinity (a
total of seven salinities ranging fromFWto SW). The water was
vigorously aerated until eggs hatched (typicallywithin 10min of
immersion) afterwhich aerationwas reduced and newly hatched
Artemia nauplii were added. Hatching success of eggs that had
developed through 14 days of incubation was >90% regardless
of salinity and larvae were fed Artemia nauplii ad libitum daily.
All toxicity tests were initiated with 7-day-old fish.