Where was it leaking from?
Drain plug
Hot fitting on backside
Cold fitting on backside
Element gasket
Pressure Relief Valve
Tank
Different causes/fixing for different leaks
Pressure Relief Valve leaking is typically due to loss of 'air pocket'.
Air pocket allows for expansion of water as it heats without a significant increase in pressure.
Without the air pocket pressure will increase when water is heated causing PRV to weep
Also could be because of hard water scaling causing PRV to weep....Open via lever and let it snap closed a couple of times to clear valve seat.
But probably air pocket
Fittings....check for tightness....replace washer
Drain plug......remove, chase threads to clean them up install new nylon plug. They come 2 to a pak
Electric element gasket..check tightness....replace gasket
Tank.....ID leak and have it repaired (aluminum welded)