Refresh postgres database on nightly basis
If you're ok with the development db being read only you could use replication using wal shipping. Instead of continuously shipping, do it on a daily basis. 

See: 25.2. Log-Shipping Standby Servers

If you need it in write mode it makes things a bit more complex as you'll need to keep the prod copy in read and clone it. 
If your storage subsystem support snapshots than it's trivial. 

Btw, 90gb should clone pretty fast - how long does it currently take? What disks are you using?