its the petalburg gym and/or gym 5.
Pokemon ruby where is the 6 gym
simply go back to petalburg where your father is gym leader and you must challenge him
roxanne, brawly, wattson, flannery, norman.
journey again to achieve the another battle called the 8th gym Pokemon ruby
In the 8th gym. he is the gym leader
Wattson the electric gym.
The town in which the third gym is in on Pokemon ruby is in Mauville City (or town, I don't know which one)
In Pokemon Sapphire, Ruby and Emerald the 7th Gym that's located in Mossdeep City has Psychic type Pokemon.
it is Mauville gym
The Fourth Gym is in Lavaridge City.
in sootoplis