Unfortunately, my Sea Nettles have not been doing well. They started to decline about a week after being put in their tank. Im still not entirely sure what went wrong, but I have my ideas. The first jelly I put in my 9 gallon desktop tank is doing great. One other I put in there is doing well also. Thinking back, I used reverse osmosis water to drop the salinity in the 20 gallon kreisel. I didn't think about it at the time, but such a large change in salinity probably nuked the bacteria in the tank. The filter is pretty much useless at that point. Then the ammonia climbed slowly, and shot up eventually. This explains the ratty, tentacle-less Sea Nettles that I found in my aquarium.
I currently have three jellies, as of writing this. One appear to be everting. the other two are doing really great. Its pretty frustrating to see this happen. I'm really hoping I can find some polyps in my desktop tank. That will make all of this work worthwhile. I just need one single polyp. With three jellies, it is quite possible that I wont have a male and female. I guess we will find out soon though. If I cant find polyps, I may be able to have someone send some to me. Either way, I will likely restart my try at Sea Nettles with breeding. Polyps are often more stable, and you learn so much about the jellyfish themselves through breeding.
Very soon, I will be building an identical copy of my first moon jellyfish breeding system. That will give me the chance to build a guide on how to build it! Hopefully that will come in handy for people. If I can manage to get some Sea Nettle polyps, then I will likely build a third similar system to raise them in.