Craig Watson, Director of the Tropical Aquaculture Laboratory, wrote me back with answers to a few of our questions:
We have a paper in review with Marine Genomics outlining reproduction, but here are the highlights:
They are marine spawners (we are using 33ppt). The eggs are 0.5 mm in diameter, pale yellow, and become adhesive within minutes after hitting the water. At 78 degrees F, they hatch in about 72 hours. The fry do not eat for the first three days, and on day 4 start eating rotifers. On day 4 we started feeding artemia. After a few weeks we ween them onto flake food.
They are very fecund, having 20% of their body weight in eggs. A 10 gram female will produce over 7,000 eggs.
The females are fairly obvious when gravid as they are much fatter than the males, but we have gotten sperm out of what we thought were "females" (they were fat males). I recommend taking them off feed for a few days before trying to sex them as food in their bellies can be easily confused with eggs.
We attempted natural spawning for over a year, and then standard induced spawning techniques using injections, all to no avail. We developed a new technique (which we will also be publishing) we are calling "ovarian lavage" whereby we flood the ovaries with HCG, a spawning aid, and the females are ovulating ~36 hours later. We are then expressing the eggs and sperm into a bowl, adding seawater to trigger the sperm, and then broadcasting the eggs into aquaria.
We just spawned several of our first generation fish that were 11 months old.
The methods are not suitable for the average hobbyist, but we are working with several experienced producers here in Florida to have them available in commercial quantities in the near future. If anyone succeeds in a natural spawn, I would be interested in hearing about it. I chased freshwater spawning based on some early posts on your forum and some anecdotal info from Maylaysia, but assure you they are marine spawners, as the sperm is esentially nonmotile in fresh, and very active at 33ppt.
Hope this helps.
Craig Watson, Director
Tropical Aquaculture Laboratory
University of Florida
I'm pretty impressed that the tried some ideas from the forum first