The police say there have already been around 60 such incidents this year.
Sgt Simon Reason said: "It's very difficult for the staff to deal with confrontation because they're not used to it."
In June three youths were arrested under the Protection from Harassment Act after abusing Lido staff.
Sgt Reason said he had organised highly visible summer holiday patrols of the area to try to stop youths breaking in.
"The complaint from kids is that there's nothing to do. We do not want to stop them from having fun but we do not want them having fun in a way that is a nuisance to others and a danger to themselves."
Rushmoor councillor Mike Roberts said both the indoor and outdoor (pictured) parts of the complex had experienced problems this summer.
"I have received complaints and have been in contact with the police and youth services.
"There is anything between 12 and 15 people and that has caused problems late at night."
He said staff felt intimidated, especially on Friday and Saturday nights, and residents, particularly in Guildford Road and The Avenue, had been disturbed.
"There's an issue of staff protection. You cannot have a situation where women doing their jobs are being threatened or abused — verbal or potentially physical abuse."
Mr Roberts was aware police patrolled the site, which is partially ringed with razor wire, but said they could not be there every night.
"The big problem is that if people know when they're (the police) not about, they're (the youths) straight back in there."
David Clifford, Rushmoor's executive member for leisure and promotion, said a minority caused trouble for everyone else, adding: "The biggest problem we have is the parents.
"The trouble is that the police take them back home and get as big a mouthful from parents as the kids.
"You have reprobate kids, and they come from reprobate parents."
Cllr Clifford said the council, the police and contractors DC Leisure were working together to combat the situation.