I got problem with my tank spec.

[Dexarth]

Yo

I were today in Sarth 3D, 10man, and I realised i just cant hold aggro on my current spec. i got about 30.4k hp unbuffed(31.6k while in blood spec) this is my spec: The World of Warcraft Armory (http://eu.wowarmory.com/character-talents.xml?r=Stormscale&cn=Dexarth&gn=Afterlife) I really like being blood, but i can handle frost too. and I'm a bit confused 'bout the DK rotation. so, all tips would be great. since I want move on tank ulduar :) , but i just dont feel ready yet.

So in that 3D, i tanked Sarth, i did everything i could, but mage toke aggro wiht 3 hits, we tryed that few times, but still i lost aggro, i used DaD, IT, PS, HS, DC DC, but still lost aggro :/. So, can some1 tell me is there something wrong about my spec, or is it just I suck as tank.

[vine]

Your spec is all over the shop. You're missing key talents, and have some superfluous ones.

3/3 Subversion is a huge buff to threat.
3/3 Imp Rune Tap: this is up to you, but if you are bothering to put 1 point into Rune Tap, you might as well get Improved.
Spell Deflection is lacklustre for the points investment, you can pull the points out.
Imp Blood Presence is negligible healing, pull the points out.
3/3 Imp Icy Touch is added mitigation and essential (imo).
Morbidity and Ravenous Dead are mostly wasted point for a Blood Spec

Now for Glyphs, you are Glyphed for Obliterate, which should never be part of a Blood spec rotation because it consumes diseases. D&D Glyph is also kind of a waste, Blood is all about single target threat. Try Rune Strike, Blood Strike, and Disease Glyphs (Glyph of Disease means you can reapply your diseases by only using Pestilence. Only using one unholy rune gives you more freedeom to spam HS and DS), your threat will increase substantially. You also have no Minor Glyphs, try Pestilence, Horn of Winter, and Blood Tap.

Now for gear, Blood benefits a lot from Expertise, you should have at least 26. With only 9 you will be dodged and parried a lot, and if you cant hit the boss, you can't enerate threat. You should swap out some of those pure stam gems for exp+stam, get yourself the trinket from Azjol-Nerub to replace the Repelling Charge, your defense is over soft-cap anyway.

Boss rotations might look something like: D&D - IT - HS - PS -DS - HS - DS