do I need to go to a special chiropractor?

yes

Don't let them use the electrical muscle stimulation machine (sorry, I can't remember the actual name) because amniotic fluid conducts electricity so it's obviously not good for the baby. Regular massage chairs and roller machines are ok though.

I've never used a machine. Just hands on. tried getting a massage but it's skeletal

I go to a regular chiropractor, he just adjusts around my stomach

is that considered a "prenatal visit" or a specialty visit.