Does Caffeine affect Goldfish

Description of the Project

In this experiment, caffeine was put into the vicinity of goldfish to determine its effects. The purpose of this experiment was to find out how caffeine affects goldfish, as people drink caffeine every day and without thinking about it, pour their unwanted coffee down the drain, leading to the sewers and the environments where fish survive. I also could not find any reports or information regarding this topic. The general procedure is to set up two tanks, one for a control and one for the experiment, place three goldfish in each, give the experiment fish one 100mg tablet of Wake-Ups caffeine, and observe their activity over the course of one hour, taking heart rate measurements at the five, fifteen, thirty, and sixty minute time intervals for ten seconds. The data I recorded supported my hypothesis which stated that the heart rate and the activity of the fish would both increase from the caffeine. The fish's heart rate increased by the five minute mark and returned to previous levels by sixty minutes. The fish's activity also increased during the duration of the hour, becoming more frantic with peak activity between the 15 and 30 minute marks. Activity returned to previous levels within the course of the hour. Throughout the experiment, I made sure that all six goldfish were in appropriate sized tanks, with appropriate ammonia, nitrate, and pH levels so the fish were in favourable conditions. I also made sure to feed the goldfish appropriate amounts of food. The conclusion of this experiment is that caffeine does indeed affect fish negatively by increasing their heart rate and activity which causes stress eventually resulting in disease and fatality. This experiment is the first to test the effects of caffeine on fish. This experiment and the associated tests have led to more questions: What would be the effects of caffeine on other types of fish, such as salmon? What would happen if the amount of caffeine given to the fish was increased or decreased? How much time would it take in the wild for a fish to be exposed to the 100mg amount of caffeine?



The  Regional Science Fair is to be complimented on their formation of a new Ethics Review Committee to evaluate student projects involving human and animal experimentation.

Thank you for your request to review this project from the perspective of whether this project lies within the Policies that govern science fair projects in Canada. This abstract describes an experiment of administering caffeine to goldfish and observing the effects on their heart rate and activity levels over time.


1) Use of vertebrate animals in pre-university research: Youth Science Canada Policy 4.1.2


Section 2.3.b. Pre-University Use of Animals

Primary responsibility for animal use at the pre-university level lies with Youth Science Canada, which requires compliance with the Canadian Council on Animal Care (CCAC) guidelines in the conduct of biological research, and regulates animal experimentation in Science Fairs … All research intended for Science Fairs must be screened by a committee cognizant of current requirements.


Section 6.2 The Adult Supervisor is responsible for ensuring the safe and ethical conduct of project involving the use of animals. Youth Science Canada strongly recommends that a Regional Science Fair Ethics Committee review all proposed research involving animals before experimentation is started. Projects involving animals, whether vertebrate or invertebrate, which are deemed to be unethical, may be disqualified.


Section 8.1 Vertebrate animals (i.e. fish…) … are not to be used in any science fair projects, with the following four exceptions….

d. Projects involving animal experimentation may be conducted under the supervision of research personnel employed by a University, Hospital, Government Organizations or Agency, or Industrial Laboratory and where the animal experimentation has been pre-approved by a Scientific Review Committee (SRC or equivalent) in the institution employing the supervisor.  


In the current abstract, there is no description of the experimentation being conducted under the supervision of research personnel employed by an accredited facility with pre-approval by a Scientific Review Committee.


2) Use of a drug in animal experiments


Section 10.1 Definition of a “drug”: “drug” includes any substance or mixture of substances manufactured, sold, or represented for use in:

a. the diagnosis, treatment, mitigation or preventions of a disease, disorder, abnormal physical state, or its symptoms, in humans or animals,

b. restoring, correcting, or modifying organic functions in human beings or animals;

Drugs may be used in any experiment exhibited at a Science Fair only if carried out in a Hospital, University, Medical or other similar Laboratory under the direction of a Scientific Supervisor. The Wake-ups 100mg tablets containing pharmaceutical grade caffeine falls within this definition of a drug.

In the current abstract, there is no description of the experimentation with this drug being conducted under the supervision of Scientific Supervisor employed by an accredited facility.

This project, as presented, does not meet the policies of Youth Science Canada for presentation at science fairs.  We know this will be a big disappointment.

If there is time, we suggest that the study be  repeated  on an invertebrate, where there are no restrictions on the use of drugs.  At the same store that sells goldfish, they usually have glassworms, daphnia or brine shrimp sold as fish food. These are inexpensive and acceptable.