Probably should check with the condo board first, they might be the biggest restriction and even may have the answer you're looking for. With the addition of cement floors I would feel safe with up to 200 gallons of total water provided it was against a load bearing wall and perpendicular to floor joists. But I'm not a structural engineer just mechanical so defiantly no expert.
If you have a party don't let everyone crowd around the tank at once
