Hi Richard,
even if they are still coughing sometimes, I'd now raise the temperature up to 86-88°F. This will stimulate their appetite........and I'd already use wormex for the second treatment, what you can surely imagine
It's cheaper, safer and trustier working against all worms hatching because of a longer lasting possiblity of treatment.
If you want to use tremazol also for the second time, you should do the second treatment after only 5 days and also a third treatment after only 3 more days, which means 8 days from the beginning of the measure. The information given on the instruction leaflet (even on the german one, I think, there is the same info on the english version) is not appropriate for your water temperature and will not kill all worms hatching until laying unreachable eggs themselfes again, cause it's dedicated to the development of gill worms at lower temperatures!!
Regards
Stefan