Any particular mood you're going for for your tank? Any inspirations? Since you've got bright colorful gravel, something more unnatural like SpongeBob could work as the above poster mentioned, or a sunken ship theme/ beach theme.
I like the idea of a beach theme!
Oooh! A beach theme would look nice with those bright platys!
Replace the substrate with sand and make palm trees like this (https://www.youtube.com/watch?v=LaCW9UIMNwg) except make the sponge shaped like the palm tree leaves and then dig a "stream" down the middle of the sand and put the blue gravel to simulate a river in the beach
It could be a fun movie theme - some that popped into my head:
Pirates themed - Pirates of the Caribbean
Atlantis the Lost Empire
I also like the idea of a beach scene!
Do an Asian beach! The rocks in the back would look great in an asian theme. Maybe a jungle backdrop. Thatd look amazing
Hey, that is my theme!
SpongeBob is bae
Ooh, Atlantis theme sounds cool, especially with the background the OP has right now.
Separate names with a comma.