How do you handle humidity in smaller apartments with larger tanks?

I live in an 800 sqft apartment and have a 120g w/55g sump, 2x10g, and 2x5g tanks running at the moment and I estimate that combined I lose about a gallon to a gallon and a half of water per day to evaporation. The tanks have been running for a few months and while I have not noticed any problems with the paint or drywall, I have noticed a lot of condensation on my windows this winter. It it so bad that it beads up on the panes and forms puddles on my floor and grows mold around my window and door if I don't wipe it up at least once per week. Granted, this happened before, and maybe it is just because I am conscious that humidity may be a problem, but it seems to be worse. Thinking it may be a sealing problem with the window and door as they are 10-15 years old, I brought it to the attention of management an they replaced the entire window unit and added weather stripping around the door, but it does not seem to have helped at all. I rarely heat my apartment during the winter and it stays between 69 and 76F. The lows at night are usually in the 30s, so nothing extreme in terms of temperature differentials.

Does this happen to you? My parents had a similar number of tanks in a room while I was growing up in Pennsylvania, but I never remeber seeing any condensation on the windows, but it was a much larger home so it may have been able to dissipate better.

Maybe I just need a fan to circulate the air better....not sure, but I need to find some solution as the mold is concerning.

Since I'm not having moisture accumulating anywhere but my windows, I am going to try to avoid the dehumidifier route due to cost and noise. I just hooked up some computer fans that are blowing across the windows so maybe that will provide enough circulation to keep the condensation down.

Heating is not the problem. With no heat, I average about 75F during the winter. It has been 20F here for a few days now and with no heat it has dropped to 67. Even before adding my aquarium, it rarely dropped below 73 in the winter. Sounds like mainly circulation or a dehumidifier are my options. I dont want to heat my apartment to 80, its already warm enough that I have to open the windows from time to time.