new tank here, some questions

[Nicobo]

...My gladiator is currently level 22, and up until now I never had any issues tanking...
...Is it true that a black mage that doesn't let up can sometimes make it impossible to get hate back?...

I think at low-level it would not be too hard to pull mob away form the tank,
just burn all CDs at the same time with a quick initial attack, you can make your tank like a fool,
and I found some dps really enjoy to "DPS-race" against the tank ^^;
Maybe you can try run to next group and pull quicker when this group is going to finish as one GCD ahead others is very helpful.