This is tricky. Hoping the Viej pair are good parents able to fend off any predators if not, the fries might be food for other fishes in the tank. A 2 ft tank is way too small for 2 pairs of dwarf to spawn at the same time.(My views).
If the tank is heavily decorated, chances are the line of sight may have been lowered which is good. On the other hand if the tank is open it might reduce the chances of fries survivability to almost none.
There can always be exceptional happenings, i'll not enforce hard & fast rules since there isn't concrete evidence.
My guess:
1)The highest percentage(of fries survival) if the male and both the pair of taenaitus are removed.
2)High percentage if pair of taenaitus are removed.
3)Low percentage if left alone.
4)Almost no percentage of fries survival if there are other occupants in the tank like 20 cardinal or equivalent.
Cheers!
Bookmarks