If it's thick it's hard to see the bubbles, especially just at the top surface because they just look like cracks. The white stuff is SCOBY, symbiotic cultures of yeast and bacteria. It's a good thing for next time you try.

And a very common misunderstanding for newbs!
I ACTUALLY HAVE MADE MOLD!! And was very excited to report it but just never have yet. But now IS the time. How I did it... I ferment 2, 18 gallon totes with 50# each on altering schedules so one gets fed while the other ferments. Which I have discovered, even with a decent back slosh will NOT ferment 50# overnight, hence the 2nd tote. So I sold about 14 of my hens and my feed consumption was way down. SO I just added some water to my 2nd bin to "keep it covered" as some claim you must to prevent mold. Quack! After a few days of just swishing the bin to break the surface of the water.. I could see molecular type chains forming on the surface, looking similar to connected snow flakes by the end. But more than that, I could SMELL the MOLD! Now, my guess is that what was in there had consumed all it's sugars and... well, I just don't know. Anyways, I decided to go ahead and add my 50# bag and see what happened. Well, within a day or so it looked and smelled like a lovely ferment and I fed it out. That was several month ago. So yes, you actually CAN get mold.. but it took special circumstances that didn't allow my original bacteria to out thrive the newer colonies.
Now, on to this whole leave water on the top to "keep it from molding"... I say hog wash!! And I have wondered this for a long time... Thing is that the water doesn't stay pure h2o when sitting 'on top' of the ferment. It has all the same stuff in it as the ferment, it's just separated to the top without the solids. Plus it's not like water is antibacterial or doesn't grow things in it. I mean NOTHING grows without water does it?!
My fermented feed ALONE has kept my recently disabled (no use of legs) chick alive for 12 days with zero standard water intake!!! Maybe he would still be alive if I were only wetting the feed, I don't know. But it has been nice to have the opportunity to take the time and try and decide which path I want to take for him/her. I will say the poos are still pretty normal but I do NOT expect recovery at this point. All though it isn't ideal, I don't *think* the bird is in extreme discomfort while waiting for me to do one thing or the other, as indicated by response when handling. And darn it, it's hard to cull after working really hard to save a life.
