I think they removed one awhile ago so there's just one?

is right. Euclid's zapper took out the old one (which was run by Confucius, a Dusk Terracoon). They both were in Darkside. Euclid's is on the right side of the map, and the other pet zapper is now the pile of ash on the left side.

Actually Euclid's zapper is on the bottom left side of the map right next to the pile of ash.

I was a bit confused by this too! Here's a summary.

-Confucius used to operate a pet zapper; however, the zapper was destroyed by Euclid. -Confucius's zapper used to cost 5 tokens per zap and it was once every 4 hours. -He came back during Survival and offered new virus strain zaps. -News article from the destruction of the original zapper -The ultimate pet zapper is run by Euclid and it used to be referred to as Pet Zapper v.2. -The ultimate pet zapper cost 15 wizard tokens, but it can do more than before. There is also 400k sP option for a guaranteed experiment pet. -Here is the ultimate pet zapper!