Introduction: Poecilia Reticulata, more commonly known as guppies, are a relatively common type of fish found all over the world. The fish can live in freshwater, and is easy to take care of, due to the fact that they are adaptable and can thrive anywhere. Males can get from 1.5 to 3.5 inches long, while females can get 3 to 6 inches long[1]. Males usually have lots of colors, while females are usually colorless. Guppies can eat most food that fish can eat. Our Project involved getting a fish tank full of fish that were unknown to us. We had to research the fish extensively and create a research experiment to further our knowledge about the fish. For our experiment we replaced our Pterophyllum scalare (Koi Angel Fish) with Poecilia Reticulata (Guppies).
Research Question: Does type of food affect the growth rate of Poecilia Reticulata?
Hypothesis: Frozen food will yield a greater growth rate than flake food.
Null Hypothesis: There will be no drift in growth rate when feeding flake food or frozen food.
Alternative Hypothesis: Flake food will yield a greater growth rate than frozen.
Independent Variable:
Type of food |
Dependent Variable
Length of Guppies |
Control Variable
Temperature, Water Quality |
In our experiment we fed guppies a certain amount of food and sedated them to measure their length from mouth to caudal fin. By measuring the length of our guppies, we were able to see any difference in size between the two tanks.
1. Create a small “Recovery Tank” by mixing water from both of the tanks the guppies are originally in. (Figure 2) 2. Fill a petri dish halfway with water from the initial fishes tank. 3. In a small beaker or container, mix a small amount of water with 4 droplets of clove oil. (Figure 3) 4. Acclimate the fish to the petri dish. 5. Spread the mixture around the petri dish with the fish inside. 6. Document measurement of fish by aligning a ruler with the fish and taking a picture. Measure in centimeters. (Figure 1) 7. To wake fish up, acclimate the fish to the “Recovery Tank” and run water over its gills with a plastic pipette. 8. Leave in recovery tank for a few minutes to allow the fish to fully recover. 9. Repeat steps 1-8 for each fish to get an accurate representation of the size of fish in that tank. |
Discussion:
The current data has supported our initial hypothesis because guppies that were fed frozen brine shrimp food were larger than the guppies that were fed flake food (Figure 4). Although there were many control variables, some confounding variables may have been present in our experiment. Some of these variables include, but are not limited to, age of sexual maturity and only measuring fish length without also measuring girth. Guppies many be growing in a different area than we’re measuring them. The guppies may have already reached their sexual maturity and may not be changing their rate of growth. This data may not be enough to support our initial hypothesis, which is why experiments will continue until sufficient data is found. |
Literature Cited:
1. al, Nico et. “Guppy(Poecilia reticulata.” FWS, U.S. Fish and Wildlife Sevice, Mar. 2011, www.fws.gov/fisheries/ans/erss/highrisk/Poecilia-reticulata-ERSS-revision-July-2015.pdf.
1. al, Nico et. “Guppy(Poecilia reticulata.” FWS, U.S. Fish and Wildlife Sevice, Mar. 2011, www.fws.gov/fisheries/ans/erss/highrisk/Poecilia-reticulata-ERSS-revision-July-2015.pdf.