Need help with low tuning

[Breslin dp]

I'm the new bassists for a Metal band that does a lot of low tuning, and I play a five string. I am keeping my B tuned to B, E to C what should I tune the rest of my strings to? Please help me!!!!

[crack-boom]

i would think that if youre not changing the B at all then just keep it BEADG

[ThunderSix66]

If you're keeping the B at B, and you're tuning the E down to C that doesn't make any sense at all. C is only a half-step above B so you only get 1 more note with the low B now. If I play with people that tune down to C, I'd tune every note up half a step.
C F Bb Eb Ab.

Or buy heavy gauge strings and tune:
G C F Bb Eb.

I almost always keep my tuning in 4ths as you can see, rarely drop tunings.