How do live plants affect the nitrogen cycle in a fish tank?
How Did We come Up With Our Research Question?
How do live plants affect the nitrogen cycle in a fish tank? We came up with this research question by taking into account our sticky situation with 16 Jewel Cichlid fry(babies) and not being able to turn on our mechanical filter because of it. Freshwater plants can help reduce the ammonia, nitrite, and nitrate levels in a fish tank, acting as a natural filtration system.
Project Description
We will be gathering data for a total of around 2-3 weeks, the first week and a half testing the water quality with the fake plants inserted in the tank (no filter on & no water changes) and the second- third week testing the water quality of the tank with live plants (no filter & no water changes). The fish will be regularly fed twice a day and the bubbler will be kept on so that the water recieves oxygen continuously.
Our Hypothesis
Hypothesis: Live plants will decrease nitrogen levels in the aquarium compared to artificial plants.
Alternative: Live plants will increase nitrogen levels in the aquarium compared to artificial plants.
Null: Live plants will have no effect on nitrogen levels in the aquarium compared to artificial plants.
Alternative: Live plants will increase nitrogen levels in the aquarium compared to artificial plants.
Null: Live plants will have no effect on nitrogen levels in the aquarium compared to artificial plants.
Variables:
Controlled Variable:
Controlled variables are things that you can keep constant in an experiment.
Independent Vocab:
Independent variables are things that you can change in your experiment to get different results.
Dependent Vocab:
Dependent vocab is what you will end up looking for throughout your experiment.
Our Controlled variables:
What we had under control in our experiment was feeding our fish everyday, and doing a water test every tuesday, and thursdays.
Our Independent Variable:
We changed our artificial plants in our tank with water plants to see how it would affect the water cycle in our tank.
Our Dependent variable:
What we were collecting was the water cycle levels in our tank, and how they would change. Which was the ammonia, nitrite, nitrate, and ph levels.
Controlled Variable:
Controlled variables are things that you can keep constant in an experiment.
Independent Vocab:
Independent variables are things that you can change in your experiment to get different results.
Dependent Vocab:
Dependent vocab is what you will end up looking for throughout your experiment.
Our Controlled variables:
What we had under control in our experiment was feeding our fish everyday, and doing a water test every tuesday, and thursdays.
Our Independent Variable:
We changed our artificial plants in our tank with water plants to see how it would affect the water cycle in our tank.
Our Dependent variable:
What we were collecting was the water cycle levels in our tank, and how they would change. Which was the ammonia, nitrite, nitrate, and ph levels.
Methods
The picture above shows the bubbler that stays on and the mechanical filter that we are unable to turn on because of the fry.
The picture above shows the chart/clipboard we record all of our collected data on for our research question.
The picture above shows the water quality test kit that we have used throughout the roject.
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Week 1:
We started off with a 24 x 12 ½ tank, and 17 inches height. It could hold up to 22 gallons of water. It had a running filter, and a bubbler which oxygenates the water. We started off with 16 fish in our tank, and a water quality test kit. That test kit was going to give us the levels of the ammonia, nitrite, nitrate, and ph. We would take a sample of our water, and temperature every tuesday, and thursday. That was going to the be our methods for the 4 weeks that we had of testing period. Week 2: For our second week we were still going to be keeping in our artificial plants. We just started off with a water change so that everything would reset. This time we had to take out a bigger fish out of the tank, because it was hurting the other smaller fish in there. We also started feeding our fish a bit more compared to week. Which led to an early water change that week, because the levels of ammonia, ph, nitrite, and nitrate. Were getting too high for the fish which they started getting bloated, and would have led to all of them dying. So it was a forced water change we had to make, and they all lived after. Week 3: Our third week this was the week where we would start off using water plants. Which replaced the artificial plants, and we would be using the same method as the past weeks. The only new thing that happened this week was another fish was started getting aggressive, and we had to take him out of the tank. Week 4: This was our final week for data collection, and we rinsed, and repeated our past methods. We collected our data, and we started comparing with the past weeks. Which we found to our surprise not much of a change in the water levels. |
Data Discussion
The data we have collected over the past few weeks supports the null hypothesis. There was no significant change in the trend of Nitrogen levels after exchanging the artificial plants with live ones. Although the data suggests the null hypothesis, there were confounding variables that may have affected the results. The unplanned water change is definitely a factor in the results, as well as the removal of fish. (a large fish had to be removed from the tank to ensure the safety of smaller fish) Other confounding variables include but are not limited to, fish growth (affects the amount of waste), amount fed (also affects the amount of waste), and time testing (the amount of time testing with artificial plants was greater than with the live plants). A similar experiment done at the same time produced like results. There was no significant effect of live plants (figure 10) on the water chemistry compared to artificial plants (figure 9), this information further supports the null hypothesis. Some of the confounding variables include, fish death, irregular feeding, and time testing. So although our collected data supports a hypothesis it is not by any means a conclusion.
Results
Literature Cited:
Vitousek, Peter M., and Lawrence R. Walker. “Biological Invasion by Myrica Faya in Hawaii: Plant Demography, Nitrogen Fixation, Ecosystem Effects.” Ecological Monographs, Ecological Society of America, 1 Sept. 1989, www.sciencedirect.com/science/article/pii/S0269749107003089.
Erisman, J. W., et al. “Reduced Nitrogen in Ecology and the Environment .” Environmental Pollution, Science Direct, Nov. 2007, www.sciencedirect.com/science/article/pii/S0269749107003089.
Goyal, Sham S., and Ray C. Huffaker. “Nitrogen Toxicity in Plants .” American Society of Agronomy, Environmental Science Societies, 1984, dl.sciencesocieties.org/publications/books/abstracts/acsesspublicati/nitrogenincropp/97.
Vitousek, Peter M., and Lawrence R. Walker. “Biological Invasion by Myrica Faya in Hawaii: Plant Demography, Nitrogen Fixation, Ecosystem Effects.” Ecological Monographs, Ecological Society of America, 1 Sept. 1989, www.sciencedirect.com/science/article/pii/S0269749107003089.
Erisman, J. W., et al. “Reduced Nitrogen in Ecology and the Environment .” Environmental Pollution, Science Direct, Nov. 2007, www.sciencedirect.com/science/article/pii/S0269749107003089.
Goyal, Sham S., and Ray C. Huffaker. “Nitrogen Toxicity in Plants .” American Society of Agronomy, Environmental Science Societies, 1984, dl.sciencesocieties.org/publications/books/abstracts/acsesspublicati/nitrogenincropp/97.
Group Members
Principal Investigator/ Materials Engineer
Hello, my name is Lorenzo Murillo and I am the Principal investigator and the Materials Engineer. I have one brother who is ten years old and we get along very well.
As the materials engineer, I am in charge of of making the tank work properly, and knowing it inside out. Also, being the Principal Investigator puts me in charge of our group, and making sure they stay on task, know what to do, and get their work done. |
Animal BehavioristHello, my name is Alyssa Aguirre and I am the Animal Behaviorist. I am 16 years old, go to High Tech High Chula Vista, and have 2 older sisters, and one younger. I am extremely passionate about animals, so this project has been very fun for me. As the animal behaviorist, it is my job to regularly feed our Jewel Cichlids, and make sure they stay healthy by doing daily observations. |
PublicistHello, my name is Josefina Ramos, and I am the publicist. I am 17 years old and travel to and from my house in Rosarito, Mexico very often. As the Publicist, I am in charge of connecting to local stores and ask them for support and see if they want to donate materials we might need. In exchange, we will take any new products they have and want to test but not on their fish, and we are willing to test the products on our fish tank. |
Water Quality AnalystHello, my name is Parker Fessia and I am a Junior at High Tech High Chula Vista. I have a 9 year old dog at home, whom I love dearly, and an older sister named Madison who is in her second year of college at Cal State Fullerton. As the water quality analyst it is my job to monitor and maintain the equilibrium of the tank. This includes testing the water for levels of toxins (ammonia, nitrite, nitrate) and collecting data for our experiment. |
Graphic DesignerHello, my name is Angel Bernal and I am 1 of 5 children. I've grown up in a mostly democratic home/lifestyle, but am very conservative. My role as a graphic designer is to be in charge of making the outline for the website for our tank as well as the poster for our tank. I will edit the website and poster to include important information and illustrate the information my group and I have gathered. |