Your tank looks great, Walter.    I love your rock cave. 
 
One suggestion - angle your heater more on the diagonal and nearer the bottom of the tank rather than being so straight up and down.  This will reduce the chance of heated water rising straight up to the thermostat (turning the heater off prematurely) and will also give you more chance of hiding it behind plants. 
 
Hope everything continues to go well. 
 
MCT