I saw a little white in the leaves from what the photo looks like but it doesn't look bad, if you think boost it for that one plant give it a try but don't overdo it (small corrections).
Not showing sex, you can tell by looking at many different nodes, and the pistils for a female plant are very distinctive, the balls for male plants also wont pollenate till they burst open which takes them a fair amount of time to get to that point unless in flower (you can clearly tell sex before they get to this point and its usually growers that don't check plants every day that have issues with pollenation), just relax and wait for it...40-50 days is usual (sometimes later or earlier depending on the plant).
Your plants can take up to 100 with a Co2 tank but that is only for a limited time, it is preferable to keep temps between 80-90 for co2 use. A good alternative to Co2 tanks if your interested Cdd in doing this is to buy some dry ice. Turn off your extractor fan and place a small piece of dry ice in a container then pour water over it till about 1/4 way up the container your using. Place this on top of your light (use during lights on), leave the dry ice for 30mins then turn on the extractor fan, remove container and dispose of whatever is left. Do this twice a week during flower (cheap co2 and increases yields by up to 20-50% apparently). Make sure your grow room is all sealed up when you do this, door closed etc (no need to seal the vents up as long as door is closed its fine).
I was considering co2 tanks for future but they cause hassles in many ways (filling up in particular, draws unwanted attention), cost, the fact that you have to run exhaust less to maintain 1500 cubic of co2 within the grow space (less becomes inefficient), heat issues by not being able to run the exhaust as much. There are very real benefits to co2 but ill just stick with the DIY methods that cost like $8 a grow at the most.
Will be interested to see how it changes your yields though, let us know.