Hey,
My molly is hideing!! She is huge and I figured sometime soon she would be giving birth. But I haven't seen any baby fish swimming around. My molly is hiding so well that I can't just look into the tank and see her trying to hide like before. She is no where to be seen!!! Is she hideing cause she is going to give birth? Plus I need to clean my tank and I am worried that I will stress her out...What should I do? Any help is appreciated.

if you absolutely need to clean it, you could move her to a birthing tank where you'd have to leave her until she has them.

You should always clean your tank when necessary. A tank with bioload waste is going to be one of the worst things for your fish.. What kind of cleaning are we talking about? A water change and a gravel vac would not be too bad for the fish. If she is nowhere to be found, she may have died and other fish may have eaten her. Fish will not suddenly hunt down other fish and eat them, but will be opportunistic in eating a fish that has died.