My suggestion would be to buy and research the kind of fish or coral you like, instead of trying to stock up the tank.
Sorry I couldn't read up all 20 pages but if you are still talking about the 40g tank then your choices are limited. I personally went from one gold fish in a 5g tank to 10, 26, 55, 75 now and maybe going for 300 next in my basement.
Pick what you like and get the tanks for them.
Sent from my SM-N910T using Aquarium Advice mobile app
Sorry I couldn't read up all 20 pages but if you are still talking about the 40g tank then your choices are limited. I personally went from one gold fish in a 5g tank to 10, 26, 55, 75 now and maybe going for 300 next in my basement.
Pick what you like and get the tanks for them.
Sent from my SM-N910T using Aquarium Advice mobile app