I bought mine from florida-aqua-farms.com . I have had them in the fridge for about 3 years now and still get a great hatch rate. I also decapsulate mine before hatching so maybe that helps. Its pretty simple to do plus when done you can feed the eggs directly to the tank without even hatching. I tried raising them to adults but like was said it isn't worth it. Out of thousands of baby brine you might get 10 that make it. I don't think selcon is a food is it? Its more of a vitamin supplement. I used (and still do to enrich the baby brine a bit) DT's phyto to feed them. It usually takes 36 to 48 hours for them to hatch but that is with no heat at all. I do keep it lit with a little LED light though. I pour just enough DT's in there to turn the water a tinge of green. If I don't use the brine right away I keep putting DT's until its all the brine are fed. I usually make about 1/2 teaspoon at a time to hatch and feed about half of this at a time. Heres the batch I have right now, they have been in there about30 hours now so tonight I will feed half then tomorrow the other half then I will make some more next week.
That's by blackworm tank next to it