I have always tanked 10 mans---I never tanked a 25 man, although I did heal it. I was looking for some advice. I know the bosses hit harder; does that change our gemming?
I'm ~560 ilvl in my protection gear. With stam flask/food, I have around 950k health (with Lei Shen's terrible trinket). Any idea what I'm looking at in terms of boss damage? This includes heroic raiding.
Bosses generally do hit harder so you wanna try to put more emphasis on timing your sotr than you would in a 10man - You also "need" to track all the external CDs you could possibly call for (sac, cocoon, PS, GS etc) since you will most likely be needing them during the fights (specially on heroic bosses).
Things that you can normally survive without a healer might not be as easy to deal with as well.
Havn't tanked 25mans since sha of fear hc, but that's what I've picked up from then and from the bit of 25man healing I did.
For tanks not a huge amount changes. All abilities, on average, will do about 25% more damage (from standard melees to special attacks). As an example 10H Thok does average melees of about ~175k, 25H Thok melees for about 225-230k melees. His breaths do about 200k on 10H, 250k on 25H, factoring in similar CD usage for both.
What this changes is mostly that abilities which could frequently just be AM'd through may require the use of Divine Prot to survive, and abilities normally intended to kill tanks may require actual CDs to survive (and those that requires CDs in 10m may need a big CD + 20% cd in 25m). To extend further on that the few bosses with multiple high damage mobs (such as Heroic Paragons) will require extensive use of cooldowns in 25m. You will want to utilize either weak auras or hermes to keep track of single target CDs and start to make use of them.
For both 25m and 10m Tank deaths (especially paladins and monks) aren't typically the primary concern. Your EF will have less overhealing, you're health will actually dip below 60-75% in 25m, where 10m rarely does, and you will have to make use of external heals more than you may be used to, but nothing overly threatening.