So, they don't have heat? Is this why you need to purchase UTH's and thermometer/hygrometer units?
I like the 12 dollar Acurite digital thermo/hygrometer units. Cheap and accurate enough to tell me at a glance what is going on. I have a digital temp gun that I use for all tubs and cages~ especially important for tub use.
As for quarantine procedures (QT) and why they ought to be implemented, I suggest that you do a search for all of the threads. It is really very important for the health of the snakes. QT typically lasts for a period of three months, though I keep my boas and balls separated for six months given that IBD can be asymptomatic in boas for that long but can pass to pythons and be fatal within a period of two weeks. QT is really uber important.
Perhaps putting into the tub an area of aspen for the male to 'snuggle' into. Some who don't use hides seem to like to burrow.
Each of my three boas have an RBI 3x2x1 reptile cage, heated by RHP's and they also hold humidity very well. Two of my boas really enjoy climbing (one of them is the one I got from Jimi) and so I have climbing stuff in there for them. Going to different heights also affords greater thermoregulation opportunities!!
I keep my bci's at about 90F for their 'basking' spot and then the rest of the cage varies in temps lower than 90F. Ambient temps are always around 78-80F. I keep their humidity at around 60% all of the time. And, of course, I monitor temps and humidity with the in cage Acurite and with the temp gun.
I really hope this might help you and I really urge you to find the threads that deal with QT procedures. I think there might be a sticky on QT procedures in the ball python section- maybe under husbandry....
Take care.
Thanks very much will do.