Taken from [url=http://www.ghuyajil.nl/valheru/forum/viewtopic.php?t=592&amp;sid=166a20abd0bc7865b3786ea182d30ca9]here[/url]:

Get to Duke Hydraxis in Azshara.  &lt;He's a water elemental on the southern most island in The Great Sea at 80,75&gt;  When you reach him, he has 2 quests: [i:05971e7249]Stormers and Rumblers[/i:05971e7249] and [i:05971e7249]Poisoned Water[/i:05971e7249]. Grab them both. The first one needs you to kill earth and air elementals in North western corner of silithus (you cannot miss them ) and the second need you to fight the corrupted water elementals in the lakes of Easter Plaguelands after you use on them the Aspect of Neptulos. Do both of them and then return to Azshara for delivery. 

Follow up quest is called [i:05971e7249]Eye of the Emberseer[/i:05971e7249] and needs you to kill Pyroguard Emberseer, the fire elemental boss in UBRS. Kill him, loot him, to Azshara for delivery. 

Next Step: [i:05971e7249]The Molten Core[/i:05971e7249]. This quest requires you to kill 1 Molten Giant, 1 Lava Surger, 1 Fire Lord and 1 Ancient Core Hound. Obviously eaaaaasy quest IF you raid MC  Kill them, loot the dog (not really necessary ), to Azshara for delivery (ffs not in the middle of the MC raid!) 

Next step: [i:05971e7249]Agent of Hydraxis[/i:05971e7249]. This quest just requires you to get Honored with the Hydraxian Waterlords. At last a faction that actually says to you that &quot;Hey dude, get some reputation first and come over here for phat lewt&quot; and not &quot;Hey dude, do I know ya? Get your ass outta here&quot;. 

Tips for Reputation with these guys: From Unfriendly until middle Friendly you can get reputation from killing the elementals in north west corner of Silithus and MC mobs and bosses. After that though you get reputation only from MC mobs and bosses. After half honored you get only from bosses and after hald revered only from Golemagg and Ragnaros. But after you get to Honored there is no use of the reputation. In general 1 week of MC will get ya easily to Honored. 

After you reach honored, go to your big water pal in Azshara and complete the reputation quest to get the last quest: Agent of Hydraxis. You need to kill Lucifron, Gehennas, Shazzrah and Sulfuron, Kill them, loot them, return to Azshara, deliver. 

GRATZ! You can now choose one of those two: Ocean's Breeze and Tidal Loop. 

And before you say &quot;WTF crapp is that rings&quot; PAY ATTENTION TO THE FIRE RESISTANCE. Trust me it is good, it's an absolute need to have for Ragnaros and Onyxia, there are veeeeery few items that give +15 fire resistance and don't need 3k gold to make. 

This chain quest is realy easy for all who raid MC and after the second week you can easily complete it. 

Have in mind also that you have to complete this quest chain if you want to summon Majordomo Executus and thus Ragnaros in MC


And some additional info from two posts on [url=http://thottbot.com/?i=27341]Thott[/url]:

&lt;Aqual Quintessence&gt; is used to summon Majordomo in the Molten Core. Every boss in MC other than Lucifron and Geddon have runes on the ground near where they are located. When each one of these runes are doused with the water, Majordomo spawns. 

To get this water, you must grind to get reputation with the Hydraxian Waterlords. After you have reached honored, and after you have finished the quests earlier in this chain,  you can pick up the quest &quot;Hands of the Enemy&quot;. You have to kill Lucifron, Gehennas, Shazzrah, and Sulferan. Once you have the hands of each of these bosses in MC, the water can be picked up. 

The water can be picked up as many times as you want, but unfortunately its unique, so only 1 can be carried at a time. Since there are severial runes that need to be doused in MC, I suggest severial people in the raid have the quest completed.
~Nightraid, Malygos

*AND*

In patch 1.11 we're implementing a non-consumable version of the Aqual Quintessence, available to players once they become revered with the Hydraxian Waterlords. 

This item will be available from Duke Hydraxis, and should allow the weekly Molten Core runs for many players to be slightly more convenient.