What does your first sentence mean? I'm totally confused. 1000g rises? to 178???
As for the second, my handbook says that K2SO3.2H2O is soluable in 3.5 parts of water. This differs from all of the figures given so far. That is about 28%, but adjusting for the water of hydration will increase that value. I would have to figure out the contribution, but it does sound as if a 40% solution is reasonable.