[Peter Finke]

Patrick,
1. extensive breeding (young in presence of the adult) is always a risk. A third fish increases it.
2. At best you remove the adult fish when the larvae have hatched, become dark and begin to swim within the cave (= as late as possible).
3. You can do it the other way around: remove the cave with the larvae inside (as late as possible).
4. A good technique is using a round glass (about two liters). At first take the water from the original tank. Give two small snails.(Your 5 Liter glass may do, too).
5. The young feed best on Rotatoria; one can catch or breed them.
6. Alternatively, you can use Paramecium. Set up the breeding of them early enough!
7. If you have smallest Artemia (San Francisco) you may be lucky the young eating them at once; otherwise after a week or ten days. But use only freshly hatched nauplia.
8. The round glass has the advantage that you can stir up the water once a day, wait for sinking the debris to the middle of the ground, and remove it with a fine tube.
9. The water should be filled up with the same values as in the original tank, but pure osmosis-water is mostly perfect.