Aquariums? Really? Yes, really. Since the flood covered the whole earth, all of the water would either be fresh or saline--and since the floodwater mixed with the ocean, it was probably saline. So if it was saline, how would the freshwater species have survived, or how would the saltwater species have survived were the reverse true?
Genesis 7:21-22 records: “All flesh died that moved upon the earth, both birds, and cattle, and beasts, and every creeping thing that creepeth upon the earth, and every man: all in whose nostrils was the breath of the spirit of life, of all that was on the dry land, died” The first assumption—that the salinity of the oceans and seas of Noah’s day has remained constant—does not agree with the available scientific evidence. Based on a study of various factors of the past and present, some scientists believe that the salinity of the oceans may have been one-half of what they are currently (see, for example, Austin and Humphreys, 1990, 2:27, and Walter Lammerts as quoted in Whitcomb and Morris, 1961, p. 70). There is no reason that the fresh-water fish of Noah’s day could not have survived, provided the salinity of the waters was less than it is today. Leonard Brand has noted: “[W]e would expect changes in the chemistry of seas and lakes—from mixing fresh and salt water.... Each species of aquatic organism would have its own physiological tolerance for these changes” (1997, p. 283). In addition, as Brand commented regarding the fresh/salt water mixture that would have ensued during and immediately after the Flood: “[T]he less dense fresh water may not mix quickly with the salt water and it stays on top long enough to provide a temporary refuge for fresh-water organisms. Perhaps, too, many animals have a greater potential for adaptation to changing water conditions than we have recognized” (1997, p. 301-302). The second assumption—that fresh-water fish cannot live in diluted salt water—is now known to be false, as Whitcomb and Morris point out as long ago as 1961 in their classic text, The Genesis Flood (p. 387, footnote). The third assumption—that the ability of water-living creatures in Noah’s day to survive in saline environments was the same as that of creatures found in today’s oceans and seas—similarly is known to be incorrect. Many fresh-water fish have relatives that once lived in saline environments (see Batten and Sarfati, 2000). Furthermore, even today there are fish (e.g., large-mouth bass) that thrive in brackish waters such as those where the Mississippi River dumps its fresh water into the salt water of the Gulf of Mexico. Thus, in the end, the skeptics’ claim that Noah’s ark likely included giant fish tanks is wrong.
Austin, Steven A. and D. Russell Humphreys (1990), “The Sea’s Missing Salt: A Dilemma for Evolutionists,” Proceedings of the Second International Conference on Creationism—1990, ed. R.E. Walsh and C.L. Brooks (Pittsburgh, PA: Creation Science Fellowship).
Batten, Don and Jonathan Sarfati (2000), “How Did Fish and Plants Survive the Genesis Flood?,” [Online], (Answers in Genesis), http://www.answersingenesis.org/docs/444.asp.
Whitcomb, John C. and Henry M. Morris (1961 reprint), The Genesis Flood (Grand Rapids, MI: Baker).
Did Noah Take Water-Living Animals into the Ark? by Joe Deweese, Ph.D. and Bert Thompson, Ph.D. 2001 Apologetics Press, Inc.