Air conditioners and temp issues

Ok I have tried seqrching for a few days now and I cannot find an answer to my problem. I cannot get Pumkin's tank remp above 81 with my current lights when my portable ac is on. Now I need the ac for my dog who has a list of medical needs so its non negotiable. Please what am I missing? I have tried a half dozen light bulbs and I cannot get her temps right. What am I missing? I tried xhanging her 100w to a 150 basking bulb hut it was way to hot.she glass surfed in minutes to get out. Would getting a stand and raising a 150 even work?

Her set up:
Two probe thermometers
100w exoterra intense basking light
100w regualr soft white light bulb
T8 uvb tube 24"
Meah lid with three domes along the top and t8 lashed to its underside.
(Also dont mind messy tank and table yesteeday wqs cleaning day)

I think it may be warmer than your readings show. Since the probes are up on the back wall, they are reading the surface temp of the back wall. I suggest putting one right on the basking surface (hammock maybe or the high part of the log) and one over on the other side of the tank on the rock pile. You can try securing them with a zip tie or rubber band if they get moved around a lot. Those placements will give you the surface reading in the important spots. Give that a try and leave the probes in place for at least 30 min and see what you get.

Is your tank on the floor?
Karrie