mold on soil surface

So, definitely a white fuzz forming on the top of the soil. Also a little yellow "crystal" looking thing. I assume that my soil has poor drainage. Do I need to completely repot or can I just mix something into the soil?
Also, it is only happening on my plants that get indirect sun or whose leaves shade the soil. Plants in direct sun with the same soil and pots don't have it. Do I just need more light?

Thanks!

Is it white fuzz, or is it white from mineral deposits--that can happen when you have hard water that you're using to water the plants with. I'm guessing it's mold based on the rest of the description, but it wouldn't hurt to consider the other possibility too. What kind of potting mix did you use? It might be that you're watering them too frequently and if that's the case changing the soil won't necessarily help. If you are using a good quality potting mix, then I'd just try backing off on the watering.

It is definitely a white fuzz... I let my tap water sit out for several days before watering but I am not sure if this eliminates the minerals... I know it eliminates chlorine and other chemicals...
I used MiracleGro potting soil with the fertilizer already in it.
Also, I only water the plants once the soil is dry on the top which is about once a week or every 10 days or so. Too much?

Thanks!

I often have this happen when I first pot a plant with new potting soil. I have found that it does no harm, and you can just scrape it off if it bothers you. I suspect that organic matter in the soil that has been very dry molds a bit when it gets damp. I have also had mushrooms or fungi grow in houseplant soil, again with no detrimental effects. Just my opinion, I'm not an expert, but I do have hundreds of house plants.

Susan in Minneapolis

Thanks!

Wow, 100's! I can only imagine. I just started and have 8 already. Some are really growing like wildfire and some are content to look exactly as they did over a month ago. Haha.

stans angel... hey, LOL, if you need more plants I'm offering Mother of millions babies. (pic attached)

oh, but i wanted to say, i get mold ontop of my Jade soil. out of all my plants, thats the only moldysoiled one. i was thinking it was too damp, so i'm giving it more sun less water, and is doing better.

I'd definitely be interested in the babies. Let me know how we go about it...

Thanks!