Yes, I used smaller whole mysids with eyes and I shined the red light on them while gently puffing them with the pipette to get them moving a little. I will keep trying; I did not expect this to work the first time.
BTW, I do think this is a good idea. While I used the red light on the frozen, I did not do it the same as I did with the live. I will try a week of shining the light on the live mysids every night. Maybe this will get them trained on the light=food idea. Then I will switch to frozen and see if that is enough of a connection to get them to eat the frozen when it drops in.
A couple cuttles have started to eat frozen. I did two things. (1) I have been shinning the red light on food at night when I feed. (2) I also fed them a few larger volcano red shrimp (Opae ula) I have had on hand for my seahorses. I was hoping to get them used to a larger food item since the PE mysids are bigger than the the live ones I buy.
On putting some frozen in last night with the red light, a couple of cuttles ate them before they even hit the floor. A couple others needed me to move it around a little with the flow from a pipette. The rest, however, we not yet interested, so I will need to keep trying.
No, I have not seen any offspring. I have had mine in a 2.5G tank for 9 months. While they are about the easiest creature to keep, they are difficult to breed. According to Pete Giwojna of Seahorse.com, Halocaridina rubra need a salinity 1.0114 S.G. a temp of 72-73F and less than 10ppm Nitrates. They reproduce slowly (large females only carry 12 to 14 eggs at a time). They spawn but 4 or 5 times each year, and produce an average of only 5-10 larvae per spawn. They can, however, live for up to 20 years
From Pete's Book: "The larvae hatch as free- swimming, yolked zoeae after a brooding period of 38 days...[Light] triggers their four-stage larval development. Larval development is abbreviated with four zoeal stages and one megalopial stage occurring before they reach the first juvenile stage. The larvae retain a large yolk sac when they hatch, and this yolk supply is sufficient to sustain them throughout their larval development. The larval volcano shrimp normally do not feed until becoming benthic post-larvae (i.e., miniature shrimp). This transformation takes only a few days, during which the surface-swimming planktonic larvae metamorphose into post-larval shrimp, and these juvenile shrimp then settle down to the bottom and assume a benthic way of life like the adults. The newly transformed juveniles are 3-4 mm in length and look like miniature versions of the adults, except for their large eyes. (Due to their underground habitat, the eyes of adult volcano shrimp are greatly reduced and all but unnoticeable.) The juvenile shrimp gradually lose their well-developed eyes as they pass through a series of molts. In the aquarium, it takes about 24 to 27 days for the young to complete their development and become mature adults at 22°C-23°C. (Note: the development of the planktonic larvae from one stage to another, and their transformation into benthic juveniles cannot take place in freshwater; rather, brackish conditions are required for proper larval development and metamorphosis.)"
Love Pete. I was aware of the longevity and low egg count (and why I am starting the culture without a need) but it looks like I should try lowering my salinity. These were fairly young when I got them and have doubled in size so maturity may play a roll as well. There are brissle worms in the live rock that I hope are not eating eggs. The person I bought them from mentioned the shrimp laying eggs in the rock but I question her knowledge of this behavior as I believe the eggs are carried like other shrimp. If they do deposit eggs, the worms could be a problem.
Pete also recommends using lots of volcanic rock to build them their natural habitat with lots of small little dark crevices and caves. They need dark places to breed and prefer this. He recommends a dark end of the tank and a light end where some algae can grow.
I built this critter keeper-based, higher flow container. I got the idea from Richard Ross's article here. The hope is that the higher flow environment will keep the frozen mysids moving and therefore make the frozen food a more interesting target. The cuttles are only 24 DAH, and most of them seem more scared of the PE mysids then attracted to them (perhaps because the PE mysids are so large compared to them and their current live mysid food). I tried this last night with a smaller mysid and one of the cuttles did eat it as the frozen mysid moved back and forth on the gravel in the flow.