It's a bit of everything...
part of normal life... just like Paul B said...it's like brushing your teeth... for me whenever I go to pee in the early morning, i have to look/see my tank.. just normal for my feet to go around and see my tank on moonlight mode.
challenging.... whenever i see green algae, fish that is sick, coral not growing... it is a challenge to find the cause and the solution.... i learn to read a lot about this hobby... dosing, feeding, compatibility of fishes, coral positioning... light schedules.... and list goes on...
addictive... this one is tough... whenever i see another tank that is "better" than mine... it makes me drool... "i need to have that coral"... "i need to have that fish" ... i even learn how to save (hide) money for my next buy... hehehe...
satisfying....i think i have to put this too... at the end of the day, or when everyone's in bed... u just have to sit at the front of the tank, put your legs up and just relax... the soothing sound of the water... the waving hands of the corals/polyps... the "flight" of each fish... just satisfying...