This is one of the gerbil set ups I've seen in the Eco Habitat - can't see a wheel but there might be one - has a lot of substrate though and buried tunnels/tubes.
https://www.youtube.com/watch?v=kAi47sNFt30
Other set ups I've seen are on Zooplus - owner photos under the Falco cage photos section.
Might be an idea to ask on a gerbil forum - I had a quick look and opinions seem divided - some do, some don't.
I think the important thing is it's the right cage and the right amount of bedding to allow them normal behaviours.