cast exposed concrete / fix / prime

Hello,
we have a few "exposed concrete walls" and "ceilings" in our new building.
(What the quotation marks stand for is clear!!)

But no problem, we managed quite well with concrete filler.

For fixation, we used lithium water glass diluted 4:1 (distilled H2O). On the walls, that worked great, no abrasion or dust.

Unfortunately, the ceilings don’t work at all. Even after three generous applications (sprayed on), they still produce dust.

Which alternative product can you recommend? It should be colorless and not darken the concrete surfaces too much.

Thank you very much for your answers

Water glass should always work. Were the ceilings still damp? It takes a long time for concrete to dry through. Or were there still residues on it? If water glass doesn't work, I fear that sealants or impregnations won't hold either. On the ceiling, it doesn't really matter. You don't usually come into contact with it in everyday life.

Hello Rick,
The concrete is no longer damp, already 1 year old, no residues visible. The water glass also penetrates well, across the entire surface.
On the ceilings, the water glass does not completely fix the concrete; when you run your hand over it, it is slightly dusty. Even if you completely dust the spot, the next day it is slightly dusty again. I have concerns that this might be a permanent source of dust in the future. (maybe it works better on the walls because of the applied concrete filler)
If you are familiar with it, in your opinion, is there a difference between lithium and potassium water glass? Which mixture would you recommend? How many applications?

Normally, one application is enough to petrify the concrete. Lithium water glass is the "highest quality." Potassium water glass is more easily water-soluble and therefore not quite as suitable for outdoor use. Indoors, it doesn't matter. Sodium water glass makes no sense at all. What happens if you spray water on the ceiling? Does it absorb or not? If not, the surface is petrified. Then the dust comes from somewhere else.

The ceilings (but also the walls) absorb a considerable amount of water even after multiple applications of the water glass mixture. I was surprised too, because they are actually not supposed to.

That should not be the case. How much did you dilute the glass of water and how long did you let it dry?