Currently, I have 51 Dwellers, 2 power stations that are 3 rooms wide and fully upgraded. However, its gotten to a point where I'm continually running low on power. I have enough dwellers producing power but the marker that the power reserves has to be passed is so close to full that I keep not having enough power. When I have my phone on and I'm able to push to collect the power, I am able to maintain above the necessary power to keep running, but when I shut the game off(by that, I mean exit out of it completely) and come back to the game later, I am below the threshold. I think the amount of power that I require to keep running is 500 and I have a total of 600 power reserves. Do I have to build another Power Generator? I know that will increase my maximum power and I know that I don't need to have somebody operating the power room because my maximum power will be increased either way. I do prefer to have people operating each room because that means that if Molerats attack, there's somebody in there to fend them off until I can get some other Dwellers in there to help(as opposed to not making it there in time, and they start spreading throughout my Vault). Should I destroy some of my rooms or something? I feel like I'm doing SOMETHING wrong.

Build additional power stations without anybody working in them. That will boost your power storage and move that line more to the left. When you get to the Nuclear Reactor, those store a LOT of power. Be sure to train those workers' strength up as far and as fast as you can.

Nuclear Reactor, got it. svcks that would require unlocking Deathclaws as I SO do not want to deal with those. I'll just have to get enough strong weapons that can deal with them and train some Dwellers to be great people to fight them off.

I have a strength training room right next to two power rooms. I train dwellers in there and when one levels up its skill, i drag it to a power room to replace a lower skill, then the lowest person automatically goes to the training room until he/she has more than the next lowest in power rooms. This way power keeps getting produced more and more quickly with out one super soldier and a bunch of nooblets.

@ DynastyStar: One thing I did early on was to keep all of the females pregnant, and send the kids, when they grow up, into the wasteland to die. They still count towards your population, but don't take any food or water. Once you have enough population, unlock the room and dismiss the dead dwellers so your population drops again.

So the Deathclaws don't come if you bump your population count down again?

Correct

I had the same problem as you and had my marker too close to full.

My solution:

Build elevators deep into the ground.

Build power plants down there to lower the marker.

If molerats or other events spawn down there they only spread among those rooms and not my main vault so it is irrelevant.

You could also space them apart so no incidents spread

Or surround them with elevators so molerats don't appear.

Power rooms are basically the only room you can make a ton of without any repercussions since they don't take power. They make power! You don't have to staff them so other resource requirements don't rise with them.

I did basically what the post above states. Build elevators down a couple rows below your main vault (the deeper the better so you have more room to expand). This is where I keep any rooms that are not manned (storage, residence, or empty resource rooms for extra storage). As long as they are not connected to your main vault (other than via the elevator) the incidents cannot spread to where your dwellers are and it doesn't hurt you.