Help on water height going over, overflow.

[Chad]

Ok, I need to calculate the height of the water over my overflow (not yet built). Overflow will be coast to coast 18".

The tank will have a total of 18" x 15.5" of area in which the water will be flowing into. There will be a total flow of 200gph into the tank from the sump.

This is what I figured it out as.

200gph = 0.05555gps rounded to 0.06gps (for safety)

gallons converted to cubic inches: 0.06g / 0.004cu in = 15 cu in

Volume: 18" x 15.5" x H = 15 cu in therefore the height above the overflow would be 0.05376" rounded to 0.06" for safety.

Does this all sound right?