Can I bleach over semi permanent hair dye to achieve lighter roots?

back away from the bleach!!

Whatever you do don't put any more bleach on the lengths of your hair if they are white, you'll make it start breaking off!

It's not a great idea to bleach over the top of a dye as it could drive the pink into your hair and stain it so you would be better fading your hair before trying to lighten your roots again. There are some tips on various ways to do it here
http://www.hairdyeforum.com/index.php/topic,1704.0.html

When you do bleach bath the roots again make sure you don't overlap onto the white parts of your hair at all.

LauraLei, if fading the color doesn't strip all of it out- then what should I do?

What pink did you use? If it's a pastel one or one of the Bleach London ones it should fade pretty easily but some of the brighter pinks are known for lingering a long time and it some cases staining.

I would say fade it as best you can then bleach bath the roots (again, I want to emphasise that you should not overlap the bleach onto the white lengths, they've had enough bleach!) but I really wouldn't advise bleaching over freshly pinked roots as you're opening up your cuticle and you risk staining (plus you can get unexpected colour results when bleaching over direct dyes, some purples go green and the red I used to use went really bright neon yellow! )

I used Ion Color Brilliance Brights in Rose. It's pastel, a bubblegum pink on me.

I was reading up on my options for fading color. Curious as to your opinion on this female's suggestion on Youtube (partial link below). I've never heard of including bleach powder without developer, and I didn't see it posted here on the pinned discussion. It seemed to work for her and she claims it doesn't bleach in her description. I don't know the chemistry behind it so i figured i would ask.

youtu.be/eElCtWxDsRU

Also, if i do.another bleach bath should i use 30 vol developer 20, and the maximum time? I'm assuming I'd need to lift my hair two shades.

I've not got any experience with that brand I'm afraid, but if it's marketed as a pastel it should fade somewhat fairly easily.

Some people do use the bleach powder method to fade as a last resort on particularly stubborn colours after using the other methods listed, but if your hair is already bleached to white I really wouldn't use anything with either bleach powder or developer. I would start by washing it frequently with head and shoulders shampoo and see how you get on.

I'm not sure how long ago you did the second bleach that turned your hair white but it takes around a month after bleaching for the true extent of the damage to show and then the condition can deteriorate further through normal wear and tear such as brushing and styling after that, so do be careful if you did it within the past month, you may notice more damage as time goes by.

It's really hard to say about the timing for your bleach bath without knowing your hair, we usually advise a strand test but I think that would prove difficult on what you are trying to do. If the previous bleach bath lifted the yellow lengths to white then I think you may be ok just doing the same again but on your roots only,( again I'm going to emphasise that you need to make sure you don't overlap the bleach onto the white parts) and let it lift to a light inside of a banana peel yellow. You should not bleach your hair past this very light yellow stage as it risks the integrity of the hair's structure.

Thank you for the assistance, really appreciate it!  *thx*

No probs, good luck! 🙂