That will likely be too much water---it does not take hardly any to get it to 35
It takes a while to evaporate, so take the water out, then see where the humidity is at-the wet styrofoam will still have a lot of humidity from where the water was for a day or so, so wait til the humidity starts to drop, then add little bits to get it where you want. As far as the sponge, sometimes it is easier to get the humidity right by adding zero water to the bator, and a small damp sponge. The higher you want the humidity, the bigger the sponge. I cut one into quarters, then add the other pieces for the lockdown to get it up to 60-65 like Cynthia said. Wet globs of paper towel work great too. During lockdown--a helpful hint----put the sponge underneath the vent holes (usually have red plugs in them, take them out) in the top of the bator, then you can use a straw to drop water droplets through the vent holes onto the sponge withoout opening the bator. Sometimes if the humidity won't stay high enough you can plug one vent hole back up, but they need air so not both.Another way that works for lockdown---chookschick I think is the one that has this incubator cheat sheet with tips--you wad up papertowel and stuff them in the water channels then wet it down, that really get the humidity up and it stays pretty level. I will try to find a link and post it for you.
The incubator is at 14% humidity, and at 100.2 for the last 3 hours. If its the same tomorrow, I think we will be ready to add the eggs tomorrow night. 
