Social Research - Intriguing Topics

How Smart Are Fish?

An interesting experiment has occurred to me. It would be fairly easy to do, entertaining to watch, and possibly informative in its consequences.

Consider setting up TWO normal sized aquariums, say 5 feet apart, and oriented long ways (with the smaller sides facing each other). Then replace those (facing) end glass panels with Lexan or other panels where a circular hole could be cut, maybe 3 or 4 inches in diameter. Then connect the two aquariums with a clear Lexan tube of the same diameter. (Of course, make the connections water tight).

Public Service
Self-Sufficiency - Many Suggestions

Environmental Subjects

Scientific Subjects

Advanced Physics

Social Subjects

Religious Subjects

Public Services Home Page

Main Menu
Fit this out with the usual aerators and other fixtures. As for the circulating pump, get one for a much bigger aquarium, and get a variable speed control for it. Arrange it so that the circulating pump draws its water from one tank and pumps it into the other one.

What this all accomplishes is that there is an adjustable speed water current flowing in that connecting tube. The tube must be clear, so that it does not seem dark and foreboding, and not too different from the nooks and crannies that fish seem to like to explore and hide in.

After the water is stabilized, the fish are put in ONLY the UPSTREAM aquarium, and the circulating pump is adjusted so that there is very minimal water velocity in the connecting tube. Sooner or later, each of the fish would certainly swim near enough to the entrance to the connecting tube to be drawn in and transported to the other, DOWNSTREAM tank. Eventually, all the fish would be likely to be in that tank.

Assuming one of the fish either was inquisitive enough (and persistent enough) or that he decided that the tank he was in was too crowded, he might swim against the current long enough to get to the upstream tank, which would then be unpopulated. If that happens, it would establish at least a minimal logical capability.

If that particular fish started then to regularly travel between the tanks, that would show even more logic. If others started following him to get to the upstream tank, that would infer more generalized intellect, rather than just being a single individual.

Assuming that one or more of them started regularly traveling through the connecting tube, which suggests that they have an overall plan about it, after a few weeks of this, the velocity of the water flow in the connecting tube would be increased. It would be interesting to see how many of the traveling fish would still go to the effort of trying to make the trip upstream.

If a number of them still do, then further experiments could be to keep increasing the velocity of the water flow in the connecting tube, say at three day intervals. At some point, the flow would get near to the speed that the fish was capable of swimming. In that case, they might resemble Salmon swimming upstream to spawn! Maybe some would just go into the tube for the exercise, like we go to the gym. Some may try to make the trip just to dispel the boredom that might exist in fish which are forever trapped in an aquarium. I don't know if there are any other kinds of experiments possible that could try to determine WHY various fish reacted to the upstream flow the way they might. I guess that once it was seen just how they actually do react, someone could figure out further experiments.

Of course, maybe none of the fish would ever enter the connecting tube. Or, maybe they would only enter it randomly, as by accident, which would imply no logical ability. Even that result would be an advance in the cause of science.

This experiment is simple enough that it might even be possible to be done as a Science Fair Project for a young person in school. Or, it could be done with very careful scientific documentation, and be the source of a research paper or Doctoral Thesis.

It seems to me that there are INCREDIBLE promotional aspects to this as well! Say you own an aquarium shop, and business has not been as good as you would wish. You would want to get more people in your shop, right? So set up the two aquariums in a prominent place in the middle of your store! ADVERTISE that you sell the SMARTEST FISH AROUND AND YOU CAN PROVE IT! So, people come in and you turn up or down the pump speed, or whatever else is necessary to get the fish to react. Maybe that means putting some new ones of them in one or the other of the tanks. Have a big clock with a second hand, and encourage kids to time how long it is before each fish gets through the tube! Try different species of fish, or young and old ones, or a hundred other possibilities. I have a feeling that whatever fish won that sort of "drag-race" would sell for a premium! MORE, the entire community would be talking about YOUR shop! After a while, if interest fades, invite some local University's researchers to come take a look. You might get another boost of publicity if a University does research in YOUR store!

This presentation was first placed on the Internet in May 1998.

This page - - - - is at
This subject presentation was last updated on - -

Link to the Public Services Home Page


Link to the Public Services Main Menu


E-mail to:

C Johnson, Theoretical Physicist, Physics Degree from Univ of Chicago