You will need to run a dehumidifier in the basement. I would cover the tank also, 50/50 on RC about doing this, something about gas exchange, but destroying my baement is not an option, and I haven't had any trouble since doing that last fall. I have a humidity monitor and keep a watch on it, usually hangs around 40-70 % humidity. In Summer, I open the basement windows, and turn off de-humdifiers. They also sell exhaust fans, similar to bathroom fan but higher ouput, they typically use them in greeh houses. I wouldn't use one unless your humidity stays at 70 and above, you will find your cold water pipes will begin to sweat also, and black mold will soon come.