I've run my hps for 24 hr cycles before. Didn't hurt it. It's not the best choice unless you can get a heater in there. Or those T5s.
50s is fine though. My tent goes down as low as 48 with lights out. Yours will probably run much lower considering. As long as you can get the humidity down...
If you can afford it, run 24 hrs. Or just take the cool tube off. That humidity NEEDS to come down though. Can't stress that enough. Low to high 50s you want between 60%-70% humidity. Any less, they'll slow growth. Any more, they'll start to die.
And then there was one. My kid just yanked one out. The taproot came with it and a leaf ripped but I tucked it back into the soil. We'll see if it makes it.
7" tall in veg maybe. You'd have to run small clones to do that in my opinion. Almost no veg time after it roots. Right to flower. Then it'll stretch out a bit but still be relatively small.
When you flip it to flower and you start seeing calyxes, paint some colloidal silver on it. Best to do 2-4 to increase your odds. Do that every day for about 2 weeks. It'll grow balls instead.
Collect your pollen sacs and paint the pollen on the buds you want to pollinate. You could just let...