I bought a 500 gallon pressurized tank from new horizon it is a steel tank with about 4" of fiberglass insulation a 2" air space and then a sheet metal cover. The tank is rectangular. I got it hooked up and it works very good but after 2 days I seen water drips on the floor of my basement under the tank. I pressure tested this tank with air before I installed it so I dont think its leaking. The covers are pop riveted on so I drilled them out and looked under the top cover and its covered with condensation. Is this because of the moist air in my basement . I know I need more insulation but I want to be sure that I dont have a leak in the tank. I think the metal cover on top is causing my problem should I take it off and add more insulation leaving the metal cover off? Has anyone ran into this problem? I filled the tank with well water and started to heat the tank within 3 hours after filling .