For the last few weeks, I've been "building" a 20 gallon that's divided into five sections. Each betta will have approximately 4 gallons. Today, I added fish! Currently there are 2 males and female. I'm really happy with the way it turned out. It's not perfect but it works.
Fiberglass window screen
Silicone (NOT mold and mildew resistant)
Exacto Knife to cut window screen to size and to scrape off excess silicone
It is still a work in progress - the decor needs a major overhaul. Live plants will be added and more rock features. A background will be added as well!
The tank over all:
Facing off through the screening:
Currently I have two males and a female in them - watching them interact through the screen is hilarious. I wasn't sure if they would be able to see each other, but apparently they can!
The sections are quite tall but they have been using the whole space. :)
I'll be updating the thread as more fish are added and the tank is improved upon.