Similar water conditions but some areas pretty different.
There is commonality on parameters.
There are reasons to not do this, mainly the types of fish, cool water and tropical have different needs and can stress in less than optimal conditions. This makes illness a threat. Keeping up with a varied diet and good tank maintenance would be very important, and I would run really high gallons per hour in filtration.
Gallons per hour turnover in the water is tank size times 10 for Goldies.
It might be something possible until you get another tank.