I think that it stays the same. Indeed there wouldn't be enough material to form more glucose, because there would be more water and not sufficient CO2 to compensate the increase on water. But this confuses me. I learnt that increasing reagents shifts the equilibrium to the products.
Or, maybe, if I add water, there would be a discrepancy, and glucose would begin to be consumed to make CO2. Is that it? This confuses me, because I learnt that, if you add to the concentration of one compound on one side, it shifts the equilibrium to the other side.