Arapaimag built a 50,000 gallon tank at his house. He writes – “I built my mega and mini mega tanks in the 1994 to 1997 period. I built the tank as an addition to the home and then joined it by putting doors through the basement and upstairs through the bedroom. You can see the excavator removing the soil on the first week of construction. You can see the doors cut through my walls in the 3rd picture.” Link.