Tribble Herder wrote:
has more than a few examples of what are allegedly cloud tank effects shots (or at least something very close to a cloud tank).
Open the link and click the PREV arrow four times to see the example.
When I think "cloud tank" I think of the effect as per CE3K (Close Encounters 3rd Kind for you young ones) that is intended to create what actually looks like clouds, and which uses salt and fresh water to create a "floor" for the cloud effect, but using inks and dyes, etc., in a water tank probably still qualifies. That said, I'm struggling to think of another example on Star Trek
aside from Murasaki 312.
Here's a great description of the CE3K cloud tank technique (link).
As Dennis mentioned, the first documented use of a cloud tank technique in a motion picture was in 1947 for "The Beginning or the End", a fictionalized account of the creation of the atom bomb. You can see the resulting mushroom cloud effects at 4:34 in the trailer here (link)
(sorry there's an ad to sit through).
For The Beginning or the End (1947), director Arnold Gillespie…was asked to re-create the explosion of an atom bomb. Gillespie's first problem was discovering what such an event looked like, since the only existing footage of real atomic explosions was classified at the time. The crete the mushroom cloud eventually seen in the film, Gillespie remembered the way in which he had seen fake blood form billowing clouds in water when filming Tarzan movies years earlier. The effects man built a large glass tank, and after experimenting with various dyes, filmed an underwater mushroom cloud. When superimposed over the background footage, it created an impression of an explosion so convincing that the shot was used in air force training films for years afterwards.
Special Effects - The History and Techniques
Billboard Books (October 1, 2000)