able to produce 3000 or so per day per each fry
This should be 1000 not 3000. May have been a typo on my end! Sorry!
Greg, What is important to understand, is that in the 9 years I have been breeding this species, selling them and handling help calls with problems, is that I have learned that over 75% of the zosterae I sell to first time keepers of this species results in losses. Many try again and eventually succeed and many move on.
Like many others, I too have had my failures. It wasn't until we went to properly enriched artemia and properly filtered the systems that we became successful, despite about 4 years of experimenting. Studying artemia (which there is a great deal of research on) paid big dividends on both this species and other species.
There are several hurdles to over come with artemia. First is that un - enriched artemia are lacking severely in the DHA component of the fatty acid profile. This can be corrected using the proper enrichment and enrichment procedures. Second, the by product of hatching is glycerol, a perfect medium for bacteria. It is well document that artemia cultures can be loaded with bacteria. Page 114 of the "Manual on the production and use of live food for aquaculture" published by the FAO states:
vibrio sp. constitute the main bacteria flora in Artemia cyst hatching solutions."
Granted, if everything is sterile and kept sterile, then this shouldn't be an issue but that is not the case with an in tank hatcher. Thirdly, newly hatched artemia quickly loose their egg yolk sac after hatching and further reduces their nutritional value. Proper enriching compensates for this by not only packing the gut but also allowing the enrichment to assimilate within the tissues. It can also compensate for some of the limiting amino acids found in nauplii. Fourthly, newly hatched artemia are harder to digest. Many have reported seeing artemia pass through seahorse fry and still be alive. Artemia nauplii have a harder carpace than on grown nauplii that you get with enriching. Also, newly hatched don't have a mouth part and don't take in the enzymes that on grown does that can aid with digestion. Lastly, properly enriched artemia will be in the 800 to 1000 micron size range. This means not only will they be more nutrition for a given amount of mass, but the mass itself is much larger than the typical 400 to 450 micron size newly hatched nauplii. In other words, much more nutrition per bite or energy consumed.
What we found that works really well in augmenting the diet of H. zosterae is live mysids co-cultured with them. The nauplii of the mysids make an additional food source and the zosterae will also go after the adults. What is really nice about this is that the mysid eat the same food so they help as clean up crew.
As for the copepods, it really depends upon the setup and the approach. If you are looking for a one time addition and there is adequate hiding places, Tisbe sp. are probably the best. They are harpactoids and contribute to the clean up crew. If you are looking to culture them separately and feed out, then Pseudodiaptomus are a good choice as they are larger. The issue with this species is that they are a little tougher to culture.
Keep in mind that there are many out there that will tell you how easy it is to keep this species. The reality is that some get lucky but the most experienced keepers as a whole find this is not the case. Public Aquariums often do things differently, some very successfully. They should with a trained staff of biologists. But I will also counter, that many have issues as well. I don't know about this particular aquarium.
Dan
there were a few I need to find out what they mean [lol]
