Another low cost option that I just implemented today:
3 1/4" Plexiglas tubing, cut to 3" height
I thought it might be too small, but I think the mice have enough room, but not too much room. What do you think? @ShanTan @liz @tberta @LegakisL @ram_kandasamy
All together, I got 23 chambers for ~$150. That’s a steal. I wanted to see from the side, but they have red/amber colored, which is more opaque to the mice, and might be better to calm them down. In any case, I noticed the mice habituated more quickly and didn’t jump around for as long as they do in the larger rectangular chambers.
Update - 2017-12-01: I’ve used these new chambers this week, and so far I’m very satisfied. The mice quiet down much more quickly. During testing, they’re much more calm. They don’t jump and walk around the chamber, as they did previously in the larger chambers we had. They have enough room to not be squished, but not so much that they can do acrobatics. And best of all, these chambers being smaller, I can increase my subject numbers without needing another rack. If I wanted to, I could comfortably put 30 mice on this rack.
One thing I might try is to get amber/red colored rounds, so that the mice don’t get excited by their neighbors.