i need more water so im trying to fill/build out the deep parts of the lakes. so i did like a 60 x 60 one layer did instant build and now ram usage is just counting up…So the question is will it ever finish 
?
i got a lot of ram so its just a matter of time i guess? but can anyone confirm ?
In my experiments with water, I had a couple of situations where I think that the flowing water created a kind of loop; where it would flow from one part of a filling area into another part and then into a third part and back to the first. In those situations it never leveled out and the RAM use kept climbing, which is what made me suspect an infinite loop.
From that experience, I’ve concluded that altering the holding pond while water is flowing is a Bad Idea, with comparable magnitude to “hey, I’ve got my trap field which can handle that ogre for a minute or two, so it should be safe to send the whole army to clear out that camp, right?” In other words, both scenarios have a serious potential to destroy that save, lol.
I would suggest that if you do anything with water, take it one step at a time and let it completely settle before moving on. If you want to move a large volume of water, do it in small chunks – use temporary dams to allow it to fill any large channels gradually, or just dig the channel as a series of small, separated sections and then let one section fill before opening the next. For filling in the base of lakes, do the same thing in reverse; so you’d want small sections of floor to be built rather than the whole 60x60 at once.
Already moved oceans of water 
and wasent really a problem but when i start trying to fill deep waters…hell breaks loose
And small chunks just isent an option since it means i will end up with some 6000 individual buildings…and i really doubt that will do anything positive for performance >.<
for the record if you only open one side when filling new areas with water. you have minimal performance loss and i had no issues doing 40x40x6 in this fashion. would finish settling the water in like 15-20 secs
I suppose i could try and let the hearthlings build it as it would be 1 block at a time then.
Think i found the infinity loop…not 100% sure will need to test it a bit more and takes long time since its water !
But i think it happens if you need to flood an area by raising water