Cym."little black sambo" Winter watering

[mjf45322]

Hi,
I live in Dayton, Ohio USA. I grow in a greenhouse where the temps can get as hot as 100 F in the winter on a sunny day and as cool as 55F at night. I have a evap. cooler that kicks on around 90F to help lower the temp.
I have a automatic watering system that kicks on twice a week in the winter. I also have a fogger that keeps the greenhouse at a 65% humidity in the winter.
I have my Little Black Sambo up at the highest point in my greenhouse where it gets the most light so I am sure it is the hottest there as well. I have fans that constantly blow keeping any cold or hot pockets from developing. So far my catts, vandas & other Cym. like it. I get a little
rot on my cym. new growths so I have to constantly keep a look out for it and spray with physan.
Hope this gives you an idea of my conditions.
Any suggestions on how I can grown my Little Black Sambo better.
Thanks,
Mike