This morning my Coralife T5 fixture didn’t light up when the timer came on. Like no flicker, nothing even tries to start up. It’s a 24” dual bulb fixture thats 4 months old . Currently running 2 ATI bulbs that are 2 months old. So I took it apart and discovered that if I use my old Coralife bulbs or any old bulb and my one ATI coral+ bulb, both bulbs light up and it works. If I use the blue + bulb with an old Coralife bulb they will flicker and act like it wants to start but neither light up. Is this a sign of a bad ballast? Or could the one ATI bulb be bad and taking down the whole fixture? I remember having a bulb burn out on an old fixture and the one good bulb stayed lit so this is confusing me. I know ATI bulbs are significantly stronger so I’m wondering if my ballast is almost cooked and can’t handle running 2 ATI bulbs at once. Thanks in advance!