Do The Cages Need To Be Long?

Nope - the cage doesn't have to be long. I prefer square cage, just don't have the room to make one of these myself.

Wouldn't your ramp be really steep if your second level is 3x4 though? The same applies to the ramp that connects the 2nd and 3rd level

Yes it would be, but would you have the space to build a nice, low ramp? Maybe I have got it wrong....

With my cage, I had a second level. It was a 2x1 on top a 2x3. I made a ramp that was nearly 2 grids long.

Sorry, I didn't really word my posts that well either! Yes, that will work perfectly.

You should also consider cleaning. Will it be easy to clean under a 3x4? You may want to make a side open down unless you change the whole design.

That's a very valid point - Do you think it will be too hard to clean under the levels?

Oh, then that's ok! Remember to post pictures, sounds like a very cool cage

You could build a 5X4 which is just a bit bigger than what you need for six girls. Then you could do a 2x4 top.

I like the idea of a 5x4, with a 5x2 second level.

That is going to be a huge cage!!! post pics after you biuld it i would love to see it!

I don't believe you are supposed to use any trash bag liners.

For my ramp, I took two grids and bent them in a half circle. I then overlapped them into each other and used electric ties to hold them together. This made the ramp not quite two grids long. I then cut a strip of carpet and used that inside the grids as a liner for them to walk on. Does this make sense? It's hard to describe in words!