Bruce :

Check the light placement . At the farm they had light from a south window all day. Did they have overhead light when you checked on them ? At the house do you walk between the light and tank so as to cast a shadow on the water? Do you walk in and turn on a light and then walk between it and them? Warmer temps. plus more light = more active fish . If light is not the source of disruption then what about noise/vibration.