Water comes through cracks in concrete ceiling, experiences

Hello dear craftsmen,

we have a visible crack in our concrete ceiling through which water runs when it rains. Since it is a condominium community, we cannot simply open the ceiling to trace the path of the water, nor can we find the source of the water from the outside.
Now I found "Water Stop" on the internet, which can be used to seal cracks waterproof. Can this also be used on ceilings, who has experience, keyword: does the water then stand in the crack above?

Thank you very much for the feedback!
Best regards

What is on top?

But the way it looks, the reinforcement is rusting; it will be very, very expensive to repair professionally.

Above that, there are 7 more floors, which makes it so difficult to find the influence of the water. I had seen this Water Stop that you can paint over cracks to leave a small spot open for dripping out, so that you don't have to have buckets standing in the whole room?

Better make a makeshift construction with, for example, slats and a tarp

with a slope towards your bucket or paddling pool

you might be able to attach it to the threaded rods

sealing it from below probably won't work