My personal measure for DPS in T10 was always matching each ring to a HP % threshold. When the last outer ring turns blue the boss has to be at LEAST below 20% HP. If it's not below that you probably won't make it.

I'd agree with the other posters in thinking the two BLMs may be the issue. I would suggest switching one of them for a SMN or a melee if possible. With that said it should still be entirely possible to clear the fight with your current party composition. I know a lot of players tend to get distracted by mechanics to the point that they stop casting whilst handling something (I'm guilty of this on SMN when first learning fights) so I would suggest that as a focus for improvement first of all.