Question:

How thick should a slab be to support an outdoor water catchment system from rain harvesting and how much rebar if any? This tank is 650 gallons, dimensions are 56" wide by 72" high and the tank is vertical. The tank specs state the tank specific gravity is 1.2 with approx water weight of 9.9 pounds per gallon I had planned on having the tank elevated 10 inches to allow for positive water pressure when irrigating any plants. Thanks

Answer:

What gives with the water tank questions?