A friend of mine (AwesomeM96) and me are planning on testing the growth rate of guppies based on different factors. Basically the setup is going to be a 2.5 gallon container for each fish, no substrate, and 50% weekly water changes. *The container will also not be filtered or heated. How does this setup sound? Is it possible to put these fish in a smaller testing container? Also, will 50% weekly water changes be enough? The guppies are ~1/2". Lastly, which gender grows faster, male or female?