racerw: Thanks, and dang, I really wanted to see your larval fish to see if there were any early morphological differences. Wild plankton from where? Did you identify what else was in the water you collected? What housing/rearing methods did you use? Did you have to use a reduced water temp?
paka/Karen B.: Thank you so much for this information. It should prove invaluable in our attempts as we know what worked to that point. Now all we have to do is try to get beyond that.
My Observations: I have observed that several of the failed prolarval/larval fish had deformities of one type or another ie: missing or deformed pect fins(spinners), mouth developemental deformaties, spines bent/twisted, deficient oil globules, missing eye(s) etc....
I think that what we are seeing a majority of the time in the drop off rate is mearly natural selection taking it's toll. In every batch there will only be so many which will prove out to be developmentally sound thru meta.
In addition I've seen that changing environmental conditions can also have an adverse effect on developing prolarvae ie: water turbulence, pH, temp and salinity.
Your's could have just as easily succumbed to a genetic deficiency. We know so little as yet and there's always more to learn.
Update:
2 nights ago(July 4th) I had a spawn of 1200+(counted 1292 ish) so far I have hundreds of prolarvae floating in the ten gallon.
prolarval/larval Conditions:
Ammonia 0, pH 8.0-8.1, temp 80-81 deg F, salinity 34-35ppt, lights on when sun comes up(6-7am overcast dependant) off at 11 pm. Light provided by sunlight (direct from 1pm - 6pm) and a 18" 15w flour strip 10" from waters surface which is on from 5pm-11pm. I change out approx 2 gallons of the 5 gallon volume every 2-3 days and replace a quart from evap every day via slow drip. I put a very small amount of kalk into the replacement water to bring that waters pH up to 8.2-8.4 (The tank water's pH drops between water changes to 7.6-7.8 if left untreated). I've also introduced slow air bubbling into the larval chamber and fast bubbling in the sump/pump chamber to help facilitate gas exchange and water circulation.
Jungle Pete suggested that I add volume to the system by adding on an auxiliary tank however this option will have to wait as it's not feasible right now.
More as it developes it's about egg time.