Depending on how new the nodes are, they’re likely not through the vetting period yet. So that could some what account for the ~5GB/day ingress total. My two, fully vetted nodes have been averaging ~18GB/day ingress total and I have a static IP, so they’re the only two nodes on the subnet. The ingress traffic has been relatively low for the past 2 months. So I wouldn’t worry about what you’re seeing at the moment.
When/if we get another decent surge of ingress, I’d invite you to visit this page where some of us post daily stats to compare against each other to see how your traffic compare.
Also, try out the payout calculator to get details on vetting status of your nodes. The vetting process can take quite a bit longer if both nodes were started at the same time since they share ingress traffic and in periods of low ingress traffic. Typically vetting period for a single node would take 15-30 days, and occurs on a per satellite basis (you could finish vetting on Saltlake well before you vet on Asia as an example), and duration can be influenced by amount of stored data (i.e. more data means more audits). Also if both nodes are still working through the vetting process then that could double the duration.