In regards to the House of the Water Dragons, these too, like their Wind counterparts, were somewhat more rare until recent times, and this was due to the lack of the Beta type energy among the Dragon races, until more recent times. Although they did exist, as I previously stated, they were somewhat scarce to find. This was more so due to their elusive nature and preference for peaceful times. Among the Dragon races, they were known to be the most benevolent among them, offering wisdom to those that that sought them out and were able to pass their tests, often involving riddles or puzzles, and depending on the rewards, it could be a life and death situation, for they deemed only the most worthy to be deserving of their praise and wisdom, and these were the ones able to pass the tests.
Similar to the Wind Dragons, since the first aoens, they too played their roles but it was often as mediators, messengers, or even harbingers depending on what was tasked to them. Rarely involving themselves directly in conflict or wars, they preferred the solitary confines of aquatic realms, where they were often tasked with helping the first Formed Ones, learn the wisdom passed down to them directly from the Celestials. Unlike their Wind counterparts, they involved themselves much more directly, and would often communicate with the races their were overseeing. They were rarely assigned to safeguard anything aside from their own personal wisdom, because it was not something that could be stolen like the treasures and technologies guarded by their Wind counterparts. They would never have to engage in any dispute as a result and could often watch from the sidelines so to speak, simply observing the flow of energies and predicting the inevitable outcomes, and thereby making decisions accordingly, in case the need ever arose and quite often it did, for it was the way of things and the Flow of the Cycles.
The Water Dragons would often protect anyone they found in their favor, or if they had been tasked to do so, simply by allowing them insight to any major events to unfold that could otherwise jeopordize the well being of the beings they watched over. Because they were not of the original Ciakar, nor Alpha Draconians, the Dragonic species that would be comparable may be found in the KGB Book of ETS. They would be more aquatic in appearence though and resemble, the race of beings similar to the Tribe of Earth known as the Naga or Nagi. They ancient descendants of the Ashkenazim through the line of Japeth out of Esau's Tribe. Part humanoid, part Serpent, they would be similar to the Alpha Draconian counterparts, although they were unlike the original Water Dragons races that retained the high Beta energy and stayed as somewhat aquatic in nature.
Similar to the environment of the Abyss Dragons, they often sought seclusion in underground water caverns and networks, but unlike the Abyss type, they never ventured too deep and often preferred the sun whenever possible. Also unlike every other type, almost all Water Dragon races, could breathe under water, making them somewhat unique in their design by comparison to other Dragonic races. As a result you can only imagine their prowess when it came to challenging one in their own environment, being that of small lakes and oceans.
Commanding other aquatic species through the use of sonar was their primary ability aside from shapeshifting, of which, among the Dragon Houses, the Water Dragons were the greatest shapeshifters among them all almost on par with the Celestials. They allowed them to literally mimic any species they came into contact with, which also allowed them to somewhat at times intermingle going unnoticed among the races they were tasked with overseeing, or even visit one that found favor with them, allowing to communicate on their level. Telepathic in nature, they were able to read the thoughts and those that came into contact with, although knowing the language of an enemy often caused complications, if tasked with infiltration.
In dealing with mastery of energy, Water Dragons and any other Dragons, often share more than one elemental attunement, and as a result, they were many hybrid Dragons as well sharing abilities with mutiple Houses or Hives. Any time you combined the Water and Wind elements, you could end up with hybrids such as Storm Dragons or Frost Dragons. Both were known to be able to control both wind and water simultaneously with different results. In the tribes of Earth, one being comes to mind that possessed these abilities and was indeed based on the Rh- Draco blood lines of Stan Lee's X-Men. Her name is Ororo Munroe, a 'fictional' character based on the Tribes of Esau and Jacob in Africa possessing both wind and water attunement and as a result, her abilities would be on par with some of the original Dragonic races in terms of prowess and manifestation. A living electromagnetic generator that could cause atmospheric heating, generating instant electro-magnetic storms resulting in hurricanes, typhoons, lightning strikes, etc. This is why the Alpha Draconians revered the Sirian tribes and their Beta energy after losing to them during the Orion Wars, but never being able to incorporate or harness it entirely until the Terra Project on Earth, since the Avatars here are basically monkey suits that we can all use to house the energies of the tribes we are all initially derived from, and mix and match them as a result due to being on the same dimensional wavelength of the 3D-4D. The idea is to create a race of Celestial Dragons on Earth as it was in the first Aeons in the Heavens, and simply climb the dimensions on our way back home, stopping and visting the various races we encounter along the way.
For the ones who are granted the highest ranks in the Heavens among the various Celestial races, there is no greater honor given, than to oversee a newly constructed and / or hybridized race that is still somewhat learning how the Universe works and what they truly are and are meant to become through learning about how to obtain and / or balance their newly aquired energy.
Historically, among the Asiatic tribes, they were the ones most noted to have many Water Dragons listed, and among them Ryujin being the most benevolent, whilst ones such as Leviathan and Gonggong, were known to be much more destructive and malevolent by nature. I have often said, where the race would be benevolent or malevolent was often whether they were still unbalanced in their design. This often led to ruthless or malicious behavior in many Dragonic races, so it's a hit and miss when dealing with Dragons.
You need to understand that among the Heavens, the Dragons are some of the oldest among the celestial races, and therefore have been around for aeons, whilst humanity and it's tribes that have incoporated all the genetics of the Draco of Earth, have somewhat an advantage not given to some of the Originals, which were by and large only destined to exist in order to propogate newer hybrids which could surpass them. This however has led to the tribes of Earth possessing the Draco energies to become abducted by the various races in the galaxy solely for the purpose of obtaining the DNA. That doesn't include other factions on Earth also involved in genetic experimention in chimerism.
Finding Water Dragons both in the Heavens and on Earth is somewhat a task, and woe to the one who crosses them for instead of being granted their wisdom, you will be on their receiving end of one of often perplexing and tormenting puzzle traps. Think of being swept into a maze with fog so thick you could cut it with a knife, and then told to have fun finding the way out as they mock you the entire time. In retrospect, if you earn their favor, you will be granted wisdom and prosperity due to their loving nature and concern of things they care most about. Water is the primary source of Life, and they knew this the best.