I have had the same problem in the past and it's really a lost cause.
Here's what I do and works for me:
Once the pair has spawned, fertilized the eggs and the eggs hatch I transfered the whole entire cone to another breeders tank. The Foster Parents will take care of the brood as if it were their own, BUT i've found that you can NOT do this with every pair as some a more territorial than others and can associate a one brood from another. In some cases it helps to even be of the same strain. The pair that you will transfer the wigglers to have to be caring and familiar with raising young... if not they will just eat them up. It's a bit tricky, but I've done it in the past.
HTH