Should I use a personal github account or a new one to publish academic code?

You should use your real name.

My lab has a private GitHub group for internal stuff, as well as a few open public-facing projects.

Everyone in our group uses their real names or some transparent abbreviation (like jsmith) or one that matches their university email/login ID.

I feel it should be immediately obvious who each person is. It would be mildly annoying if I had to remember who allo was every time, when everyone else has easy-to-read IDs.

If I was your mentor, I would probably ask you to change it.

It's fine if you do non-job-related development on that same GitHub account, for the reasons you mentioned.

I use the same account for both.

If potential future employers consider my Github account (such as for positions involving a fair share of coding or software engineering), it doesn't hurt if they notice that I may have written code outside of my professional life, too. It's probably rather beneficial.

On the other hand, I do write some code for research where the code is not publicly visible through my Github account, so that part will not show.

I would use a separate account for a couple reasons:

• If I search for "yourname Github" it would be nice to actually find it.
• It's marginally more professional to use your real name on public-facing research work.
• It's much easier to administer. I run a Github Group for people collaborating on a particular project, and it's vastly easier to figure out who should have what permissions, be on which team, etc. if it's faintly real-name associated.
• It keeps your professional and personal coding separated. While it's sometimes beneficial for a future employer to see everything you're doing, I don't necessarily want or need someone looking through the code for my papers to also need to wade through prototype code for a personal project, or have them start wondering just how much time that social network of characters in a sci-fi series took to make. Beyond that, it also gets rid of a lot of ambiguity around what's "Yours" vs. "What was made on university time".