Who Gives A Fish Forums

Yeah, in my 100 gallon, I'm thinking of adding another lionfish, preferably a different species.

check my sig for my tank's stocking

Considering your existing stock, you've got a lot of fish already, including those two Fuzzy dwarfs.
If you're after something different, the Fu machu might be an option, but keep in mind they can be tricky to care for and a bit of a handful - still, they're small enough to work.
The Zebra lionfish might not be the best choice, as they can be aggressive towards their own kind and, in my opinion, are pretty similar to your Fuzzies.
That leaves you with the Pterois species, which are a bit larger - my personal favorites, I have to admit. I'd rule out the Volitan, though, since most of your fish would be fair game for them.
Take a look at P. antennata - they top out at around 7 inches, so if you can find a juvenile, that'd be even better. They make great aquarium fish, but do keep in mind they might see smaller fish as a snack, so you'll have to weigh the risks.
Another possibility is P. Russelli, which is a smaller Volitan species, but still grows up to 11 inches.
My two cents: go for a juvenile P. antennata.

I really like the look of the P. antennata, I've been wanting another lionfish and also a frogfish, but no one's replied to my question about keeping a frogfish. Anyway, the P. antennata is great, I love their character, that's the main reason I want another lionfish. Thanks for your help.