Did did a great job of caring for the eggs. Tonight is night #4 for this spawn. I've had a bunch of ASW that has been aging for almost 2 weeks while I was on vacation. I've been doing multiple small water changes over the last few days in the broodstock tank. I also prepared a bleached, dechlored, rinsed, and dried BRT with 5 gallons of the new, aged ASW. Made sure the temperature of both tanks matched. I set up a cut-down version of a brine shrimp hatcher/tumbler (brand new, thoroughly cleaned bottle, of course) in the BRT. Airstone under the heater in the BRT. Ready for lights out!
Right after lights out, I removed the egg ball, or what was left of it, and placed it into the tumbler in the BRT. It was not so much an egg ball, as it was two or three loosely connected egg masses. "Nets" as Tal referred to it in one of his dottyback journals. The tumbling eggs were lit with a fluorescent strip light place right over the tumbler supported on some eggcrate that spanned the width of the BRT. Within minutes, I saw the first larvae. Within just about 5 to 10 minutes, I started seeing hundreds and hundreds of them! Again taking my cues from Tal's suggestions, I stopped the air in the tumbler from time to time, let the eggs settle out, and turkey basted the larvae out of the tumbler and into the BRT proper, replacing the water I removed from the tumbler with BRT water. I repeated this process for an hour or so, until it appeared that all of the eggs that were going to hatch did hatch, at which point I removed the tumbler and unhatched eggs. There were very, very few unhatched eggs.
I took a dense culture of Apocyclops that I've been raising in a 2 gallon fishbowl (actually, these are the ones left from the last failed attempt by the fish sitter at raising them in the fishbowl kreisel -- the Apo left over from that experiment have done very, very well!) and sieved them out, and backwashed them into the BRT. I also took about 500 ml of dense live Isochrysis and slowly dripped it in, 1 drop per second. I'm leaving the lights on all night tonight, and will monitor the copepod density and phyto density closely.
EDIT: I forgot to mention that I also added 2.5 ml of AmQuel Plus.
I have some rotifers that are growing in one of my copepods buckets in the greenhouse outside, if I have to resort to using them, but I want to try to raise these larvae with copepods only, if possible.
Here are some images:
The eggs tumbling in the BRT:
A composite of stiched microscope images of one larvae:
The same larvae, taken with the DSLR and a lens on a bellows:
<message edited by JimWelsh on Wednesday, February 22, 2012 1:41 AM>