Folks:
I am getting into this thread very late and I do not know if their tails will grow back
BUT
based on three experiences with Melafix and IMHO I would:
dose with 2.0X the dosage recommended on the bottle label the first day;
dose with 1.5X the dosage recommended on the bottle label the second day;
dose with the dosage recommended on the bottle label for five days thereafter and
then commence 20% bi-daily WC's for seven days (do not introduce activated carbon into your filtration process).
The reason that I am saying "dosage recommended on the bottle label" is that Melafix is marketed in two concentrations, to best of my knowledge and belief.
The "Standard Melafix" and "Pond Melafix".
Please note that you will experience significant odor, although not undesirable, from your tank.
TR