At what age should I tell my children that Jesus isn't real?

I tell my children that Jesus will protect them from the monsters in their closet and read them bible stories at night to put them at ease though I am worried that like so many others they will continue to believe in this fairytale figure throughout their lives even after hearing the most compelling arguments which discredit the bible and shed light on its many contradictions. I am thinking about breaking the news about Santa and the tooth fairy around the age of 8 and I feel that this would probably be a good age to tell them that Jesus is a phony as well. I should have just told them that Santa will protect them from the monsters since Santa does not threaten people with hell fire and I really dont want my precious kids exposed to the types of sickening things that are written in parts of the bible. I only read them verses that will not give them nightmares about satan, hellfire, God ordering his followers to skip from town to town slaughtering women and children,etc. I have read most of the bible and know that it is full of contradictions and sadistic acts which are condoned by God so if anyone tells me this is not true then they are either lying or have not read the bible. I just feel a little foolish for telling my kids that Jesus is real in the first place though it seems to have done the trick so far in terms of helping them sleep at night.