Demand for aquarium themed coloring book?

[JuiceBox52]

I've done a ton of aquarium art pieces, and I've made coloring books out of them (printed and bound)
Before I look into getting them published other than self publishing, I would like to know if there would even be any demand for adult coloring books that are aquarium themed? Here are a couple examples (mods, delete this part if it's not allowed) which are also available on my etsy shop in my bio

 

[itiwhetu]

For me yes. I love my flower books that I colour

 

[Colin_T]

With colouring books becoming more common again, and with many aimed towards adults, I'm sure there is a market for them. It might not be a huge market but I reckon there is a market for them.

You could sell them online for a bit and see if they take off. Maybe take a few to pet shops and see if they want to try them, and maybe see if the local news agency will take some.

Have a combination of fresh and salt water fishes and organisms in the book. Try to keep the price down and see what happens.