Self-Sustaining Ecosystem

The dictionary definition of "self-sustaining" says that it's something's ability to support itself without help from anything else. Every ecosystem needs some help in the beginning, but some can go a very long time without any help from an outside party. My ecosystem that I live in is self sustaining because it doesn't need any help from humans to help it survive. The sun provides nutriens and heat while the rain provides the water everything needs to grow.

Nitrogen Cycle

The nitrogen cycle starts off with the fish eating their food. The fish then produce carbon dioxide and ammonia. While the carbon dioxide goes to plants and the atmosphere, the ammonia gose to the nitrosomonas bacteria which turns it into nitrites. The nitrites then go to the nitrobacter bacteria to be turned into nitrates which is then removed from the ecosystem by plants and water changes.

Each of these parts are a very important part of the cycle. Without any of them the cycle would not be complete, especially without the fish because they start the cycle. Without plants and water's contact with the atmosphere there would be a high carbon dioxide concentration in the ecosystem. Without nitrosomonas there would be high ammonia levels with would kill the fish. Without nitrobacter there would be high levels of nitrites which would also kill the fish. And finally, without plants and water changes all of these chemicals would be in high amounts which would be good for nothing.

Tank Update 5/10

I cleaned out my tank yesterday and cleaned out the filter the day before so it wasn't as dirty. The water was still a little cloudy but it wasn't brown. My turtle has been very hungry recently. At least he isn't eating the minnows. There are still two left. They spend a few minutes apart and then they go back together.

Dichotomous Key

To use a dichotomous key, you start with question one, then you see which option applies to what you're looking for. Then you go to the question that that option leads you to until it stops at the answer. When I created my dichotomous key I started with the algae that had the least characteristics then went on so it narrowed down and made it easier to finish. Making the key was actually way easier than I thought it would be. I didn't really have any problems.

Water Quality

The water quality steps are:

1. Evaluate site by observation
2. Capture and identify algae and insects
3. pH, ammonia, temperature, dissolved oxygen, nitrite, and nitrate tests
4. Run a panel of chemical tests (definitive tests, most expensive)

The reason for doing these steps in this particular order is by doing it least to most expensive. If you can figure out the problem early on then you can skip the most expensive tests.

Dissolved Oxygen Sources

Two sources of dissolved oxygen are plants in the water and the waters contact with the atmosphere. As shown above, the cycle of CO2 and O2 change from day to night. During the day there is more oxygen in the water because that's when the sun is out and plants are able to go through photosynthesis which releases oxygen. During the night time cellular respiration takes place which produces carbon dioxide.

Dissolved Oxygen

Dissolved oxygen is oxygen that is in the water. To conduct a dissolved oxygen test you need the kit and your tank water. First you get about 25 ml of your tank water in the special cup, then take the glass tube and stick the skinny side in the cup in the ridges on the bottom and break off the tip. The water from the cup will go into the tube and the liquid will change from yellow to blue. Then you take out the tube and swirl it and wait 5 minutes. Then you compare it to the color card in the kit to determine your dissolved oxygen level. All fish can live in 5 mg/l and up but under that is when the fish start to lose oxygen and die. The dissolved oxygen level in my tank was about 1.5 so I added more plants and filled it with more water so the filter would continue to move the water which would create more oxygen. A small pond would definitely have a smaller D.O level than a large river because the river has flowing water and the pond's water isn't moving.