I just repotted my pothos 2 days ago and now the leaves & vines are super limp. I used a mix of 50% play sand and 50% coconut husk. (Read that it worked well in keeping gnats away). When I took it out of the original pot the roots were all in the shape of the pot so I soaked it in water to try to get the dirt out and untangle the roots a little but I think I might have killed it! Any way I can get this guy back?
Sometimes my plants go through "re-pot shock" and come back. The thing I'm wondering though, is there's no "nutrition" in play sand or coconut husk for the plant. Are you planning of feeding that pothos?
BTW, is that pothos in a chameleon habitat? You might worry about him chowing down on that baby...
I don't think pothos likes having its roots disturbed too much. I've learned the hard way not to do too much to the roots when I repot one - just take it out of the old pot and put it in the new one without trying to loosen the roots.
I actually use about a half playsand-half coconut husk mix in my hermit crab tank. It makes a good base for a cactus/succulent mix. I haven't tried it on any other kind of plant, though.
I don't think chameleons really bother plants too much. Hermit crabs, however, are a far different story. They're pretty good at wrecking fake ones, never mind the real thing.
In my experience, pothos is a very difficult plant to kill. You most likely just have one that is currently going thru a pretty hard shock, which is not uncommon for any plant that has just been transplanted. Your play sand may have some foreign matter in it that is causing issues, though. Were did you get it? I have a friend who insists on putting down a layer of powdered bleach before she puts the sand down for the kids to play in because she says it keeps the cats away. If you got your sand from a sandbox, this could be the case and your pothos should be repotted immediately (after rinsing the root system well with clean, running water). Personally, I prefer to use Miracle Grow Moisture Control potting soil straight from the bag for most of my plants. I even put some in the hole when planting outdoors because it gives a good start for the new plant. If you have inadvertently killed off your pothos, just cut the stems and remove the leaves, place the stems in a jar of tap water (several nodes deep) and wait for the nodes to take root. If they do (most likely they will root), just give them plenty of time to develop good strong roots and put them into a fresh pot with some potting soil.
One last thought on this is where did the new, bigger pot come from? If it is recycled from another plant, it may have something left behind that is incompatible to the plant you put into it. If it is new, they should always be cleaned with a mild soap and plenty of water prior to use (cuz you never know what kind of nasties are in them via shipping).
You might want to check and make sure the stem wasn't snapped in the process. If so, trim a few of the lowest leaves (at the end closest to the roots) off and stick the naked end in a cup of water until it forms some roots.
Play sand is extremely fine. Mixed 50/50 with CHCs, the play sand simply packs in around the CHCs, the end result being virtually the same as if the plant was entirely in the sand. The mix you mentioned will support a very tall perched water table. What that means is the bottom several inches of your soil will remain saturated and nearly entirely devoid of air for extended periods after a watering. Since plants need air as much as water (in the root zone) the plant's ability to move water efficiently is greatly impaired, so the plant wilts. When it wilts, you think 'more water' which actually exacerbates the problem.
Your soil is the foundation of every conventional container planting, and arguably the most important decision you'll make when establishing a plant in a pot. There is a sticky thread at the top of this forum that you might find helpful. It covers a lot of ground in a short while, and it stresses the importance of soil selection in improving the effort:reward thing we could all use help with. ;-) I hope you take the time to read it and ask any questions you're left with.