Generally the water kefir grains will grow 50-100% in two days. The first batch after they've been dehydrated is typically a little slower as they come back to life and start eating, processing & fermenting. So that might be what's happening.
Hmmm, first things first - check the spring water labeling. Many times "spring water" isn't really spring water (well, it might have come from a spring somewhere, but by the time they're finished filtering and ozonating it, and sometimes adding chemicals it may not be true spring water at all) and if that's the case, there may be something in it that has harmed the kefirs & kefir-ettes :( And if it's like our well-water (our well is 'spring fed), the water may have nitrates from fertilizers and/or pesticide-herbicide run-off...and that'll hurt them, too :(
Think a bottle of beer or soda pop - if the lids not tight (or you keep opening it like I do, lol), there won't be build-up of carbonation...even though the grains are alive and producing. It's usually okay to open the jar once or twice daily (especially if you see activity and bubbles, because you might actually need to release the build-up of gas/pressure), but more than that and we definitely lose some of the "fizzy".
What you should be seeing in a healthy batch:
--A bigger amount of grains at the bottom (evidence of them growing)
--Many times (as the grains are filled with gas) a few grains will float to the top.
--Move or shake the jar and look closely - sometimes you can see the tiny bubbles going upward
--Taste. When we start, it tastes like Sugar water. As the fermentation happens it starts tasting a bit less sugary and a bit more 'tangy'.
If you've got nothing like that happening (and it's been two days, right?), then I say it's time to 'fast, cleanse and refeed' the grains.
Drain all all the fluid and immerse the grains for a few hours in pure spring water in a glass bowl - then rinse them with more spring water, and soak them again. Then rinse and add more spring water and some Sugar and let them soak another few hours. Then start over.
I use RO water to be sure there's no 'kefir killing chemicals'... for 2/3-3/4 of a gallon, I add a heaping 1/3 cup of organic Turbinado (evaporated cane juice crystals); a 'hefty teaspoon' of blackstrap molasses; 1/2 a lemon (always scrubbed under hot water to help remove any pesticide or chemicals - even if it's organic); a pinch of baking soda and two organic dates.