No bubbles in air lock

I made a batch (my second) I had no signs of activity and pitched a second time this time I rehydrated the yeast first and it was active when pitched I have a cap taped to the carboy and a temp probe and airlock taped in place with duct tape to seal everything (cap was loose), I am maintaining 68-70degrees. I haven't removed the towel around it yet to look but I have ZERO bubbles. How long should I wait?
My first batch never bubbled and i kept waiting, eventually forgetting about it for months, finally went to dump it out and try again and it had fermented. It was in a bucket so I used a carboy this time is that normal, or am I doing something wrong?

 

I looked under the towel and the activity I saw in the Mason jar I used to get the yeast going in was not even visible you would find as many bubbles on the surface of a bucket of water that had sat for a few weeks with nothing in it and gone stagnant, like putting it in the wart killed it it has been over 12 hours.

 

Bought it the day before I pitched it. It was in refrigerator overnight, then put in a Mason jar with a bit of yeast nutrient and a quarter to a third cup of sugar at 65 degrees for about 20 to 25 minutes with a clean washcloth over top. Saw plenty of activity then as I poured it into the wart. Everything was sanitized with star San then rinsed before use. Had seen very limited activity in bucket before transferring to carboy so I could see what if anything was going on and control variables better. Still everything sanitized with star san before use all the way through. Monitored temp all the way and was right where it's supposed to be. Next try I'll use different sanitizer, maybe some didnt rinse away and killed yeast.

 

Sorry about punctuation, I am used to texting, where i can't afford the time to do so or i can't keep up with the lightning fingers of the people i text. Also my sausage fingers on a phone screen makes it slow going with all the corrections I have to make.

 

So I AINT A ENGLISH TEACHER.

 

Here is how my fermenter is set up and an explanation of why.
The thermostat is set to keep it between 68 and 72 degrees.I have a small heater under the carboy to heat it if the temperature goes down enough to turn it on, only happened when it first went into the carboy.
You can see the rag in place of the plastic cap on the fermenter, I am trying to eliminate any possible back pressure that could be preventing bubbles in the air-lock.
The cap is loose so I taped around the area where it goes on the carboy.
The air-lock goes in and comes out very easily, the cap doesn't grip it, so I taped around where they go together.
The temperature probe is much smaller than the hole it goes in so I taped around where it goes in.
The towel is like a blanket to keep it warm. If the towel isn't good enough I'll use a mylar "emergency blanket".
The little foam floating is from when I activated/rehydrated the yeast in a mason jar.

 

I guess photos aren't allowed in posts.

 

I guess I overfed it and killed it then.

 

Ok thanks

 

I think I may know what I did wrong. I think I didnt aerate the wort enough before pitching. I was trying to avoid too much oxygen and think I may not have had enough. If this is the case can.it be salvaged?