You can also feed them cultured green water. That's essentially single cell free floating algae, such as Nannochloropsus. You can buy disks of this algae, Florida Aqua Farms makes them. Follow directions, add to water and grow under lights, with an airstone and some ferts.
I squirted about 100 cc of this into the ghost shrimp breeder tank I had twice a day and had very good survival rates. I started when the females dropped the eggs and kept it up until the shrimplets had morphed and were crawling on the substrate, about 3 or 4 weeks. Shrimps morphed in about 4 days, at about 72 F. Temperature can have a big effect on survival.. the warmer it is, the fewer you will have that live.
The tank CAN be fairly new.. I was caught by surprise when I first got ghost shrimp, not realizing some were berried. I wanted to raise them but I had to set up a breeder tank overnight. Used media from the big tank to get the power filter running, but also put a sponge filter in.
The cultured algae makes up for the lack of biofilm to some degree. But I also put rocks and wood in from the main tank, that had plenty of biofilm on them, and used substrate from the main tank, also well seasoned with biofilm.
Eventually I removed the power filter and left only the sponge filter going, and I was able to raise several broods this way, all the way to adulthood and breeding themselves.
Additionally, I fed them Golden Pearls in the 5-50 micron size, and powdered Spirulina, which I mixed with water first.. a half tsp. to a cup of tank water, shaken very hard in a sealed jar to mix it up and poured in. Once I could see newly morphed shrimplets floating, I also fed them banana and micro worms, which I was able to see them eat, you see the body jerk when they grab one. Between these items and the greenwater, the shrimp did quite well.
Once they were about 3/8" long, I fed them a wee bit of algae pellet or tabs once a week, as they foraged mainly on biofilm, from the sponge filter, wood and substrate, and also a few microworms about once a week. Kept a mystery and a couple of Nerite snails in with them too.
Plants were also a feature of the tank and I had a fair number of very small frogbits on top. They grew eventually but at first they provided very little cover. But there were no fish in the brood tank at all, and I removed the females after they dropped their eggs, as soon as I could manage to catch them; partly so they would breed again, partly because they tend to eat their kids, or so it appeared. I got more survivors without females than with females in the tank.
