While I have still been treating the tank for ich and keeping an eye out on the water params, there has been no sign of any white spots or ich symptoms for a week. I think I'll continue treating for a few more days just to be 100% sure everything is fine and that ich is killed for good.
All the clowns are looking healthy and are swimming and eating like normal again.

I've kept the temperature at 28C (82F) during this time, is it okay to leave it at 28C? I've read that 78F is usually ideal, but I've also read that clowns prefer and actually thrive in the warmer temperatures.
I have sterbai cories and rummy noses, so they should be able to adapt to the higher temps (28C-30C).
Cheers