I'm currently studying for the HAMNat and am facing a block in chemistry?

Why aren't polysaccharides osmotically active? I know that monosaccharides and disaccharides are highly soluble in water and osmotically active. But polysaccharides can't pass through the cell membrane either, and then the cells would absorb water… so they're osmotically active, right?

Is osmosis water the same as osmosis water or are there differences?

Very good morning. My question is once again about aquariums and osmosis water. Is osmosis water the same as osmosis water? Or are there differences? I live in Munich and want to mix the tap water with osmosis water to reduce the hardness a bit. I'm sorry if this is a stupid question, but I…