I have a 5 gallon with a puffer fish. I'm thinking about upgrading him to a 10 gallon and possibly adding some wood cats into the mix. Would that be alright?
I’m having a little bit of naming trouble here. You say you’ve got a puffer fish – which type is it? I’m going to assume it’s a dwarf puffer since that’s the only type that can live in a 10 gal. If it’s not then tankmates are the last thing to think of right now!
Then we’ve got the wood cats, a name for an entire collection of different catfish. I’m going to assume you’re talking the honeycomb catfish (Centromochlus perugiae) as this is as far as I know the smallest catfish that is referred to as wood catfish. Now, while these stay small I don’t think I’d recommend them for a 10 gallon. A 20 or so would be better in my opinion.
The only similar option that springs to mind that you could consider is Hara jerdoni, a teeny tiny, not too active and rather inconspicuous number. Even then, I’m not sure if I’m a fan of puffer + Hara jerdoni in a 10 gal. If you’ve got the space, your dwarf puffer and a few of these catfish would probably be good for a 15. You’ll have to get the hang of feeding them, though, because both just love live foods and the catfish are probably a bit more timid.
I hope that helps!
Further reading: Dwarf puffer caresheet