According to Bosskillers this is a tough guy but only just a bit more so than Grull and Mags. The one key point of this fight is resist sets, especially for the Tanks. Frost tank's average hit taken should be around: 3,100. An unresisted hit with 100% mark will typically hit for nearly 11,000. Nature tank's average hit taken should be around: 2,900. An unresisted hit with 100% mark will typically hit for nearly 10,000. On a lvl 73 mob 365 is the resistance cap so it is important to get as close to this as possible.

There are some really good lists out there the most comprehensive that I found is from wowwiki.com

Frost Tank gear guide
One interesting point for the Frost Tanks is that Bosskillers suggests to have swiftness potions as I assume that they get slowed due to the effect of the frost bolts.

Nature Tank gear guide

It also has a very good list of a mix of leather gear for Druid off tanks.

Druid Tank Resistance gear

Most strategy guides suggest that the best off tanks to have are druids as they have great dual tanking threat generation.

Hopefully this helps some for the upcoming fights

Bosskillers Portal for Hydross

This guide says that Hydross is Taunt Immune so it will be just a bit more coordination that we need to take care of.

Well Best of luck and I hope to see everyone there.

-Sleepingbag