Aquariums: I have 7 neons and 8 rummy nose tetras in my 40g. Should I add more of both, more neons, or more rummy’s?

There are 8 panda cory catfish and 5 otocinclus as well, but that’s it. I just want a huge Tetra school, but can’t decide what to get!

I would say add a few more neons so they’re more comfortable schooling like maybe 3 more but it is true that rummy nose are hardier so I’d go for those as the majority fish.