[hisnameispip]

For gerbils, I think a glass tank/aquarium is going to be your best bet. They can't chew glass, which is good because gerbils will chew anything!
I started my gerbils out in a barred cage and they chewed their way out within a week. So, I moved them to a 10gallon tank but recently upgraded them to a 20 gallon. The recommended size for gerbils is 5-10 gallons per gerbil, so either a 10 or 20 gallon is a good size. Some people like to have them in bigger tanks, such as 29 or 40 gallons, or even an Ikea Detolf. But I'm of the opinion that small is safer, as larger territory may lead to declanning with a pair of gerbils.
I really prefer the 20-gallon aquarium because it's just big enough that I have room for everything they need. There's just enough room for all of the deep substrate that gerbils require. The only downside to an aquarium is that they usually don't come with a lid- I originally didn't need one but I absolutely had to make one after one of my gerbils escaped. I ended up making it out of wire cloth and zip-ties.
I hope this helps answer your question, if you need any other gerbil information, feel free to reach out and I'd love to help!