You need Nitrogen. In other words you need to give her some nutes. If your local garden center doesnt have FoxFarm products then just try giving her some something with a sufficent amount of nitrogin. As for the soda water. I have no idea. Its prolly not a bad idea, but I would check the ph of the soda water. I have heard of using Hydrogen Peroxide for a lil cO2 boost.

I dunno, but try some bonemeal.