Hi,
Not to hijack the blackworm topic, but with such small fish, why not focus on a sustainable live food like grindal worms which are far more size appripriate and easier to keep then blackworms?
On the blackworm topic, I keep small filter media bags of peat genules in my blackwater tanks. In my L183 tank I had fed some blackworms several months ago. Appearenlty some of the blackworms made it to the filter media bags and took up residence. The end result was a breeding colony of blackworms that the fish would graze on , but not deplete.
Here’s a pic of them
[IMG]http://i1126.photobucket.com/albums/l604/AlorinDawn/blackworms_zpsf65ad79d.jpg[/IMG]