Week 4 Day 4

This morning we had a  very interesting seminar from a gentleman named David who works for the City of Denton doing water quality. He is also a meteorologist for the Navy through the reserves. I will see if I can get his power point to share here.

After that Joe, Lori and I spent most of the day working with Jennifer to improve our soldering skills. We started out making a very simple circuit with an LED and a resistor.

 After that we moved on and mapped out a noise maker circuit and put that together. Lori opted to make hers on a bread board and it turned out very well.

I went with the soldering option. Took a little longer but I am proud of the results. I just wish it was louder...

Lori and Joe have spearheaded accumulating some data from the sensors in the artificial stream. Here is what we have collected:

On Tuesday we managed to get our prototype stream system going with 15 minnows in tank 1 and 20 in tank 4. Zac added an equal distribution of plants to each of the tanks. Our gravel throughout spout created riffles large enough to increase oxygen levels. Fish migrated from tanks 4 to tank 3 and 2 but migration was limited in tank 1. We observed that tanks 2, 3, and 4 riffles have a higher volume of water allowing fish to travel upstream. In order to increase fish mobility between each of the tanks we created small channels in gravel.

Tuesday’s results- 2:30pm:
After setting up our stream we turned on the tank pump and bubbler and took probe readings after 1 hr. (allowing fish to acclimate to environment).
***note, Dr. Hoeinghaus brought his fancy YSI 600 to help us compare Spark to something professional grade. We measured our stream system and both pH and Temperature were spot on but DO measured higher- 10.

	pH	DO (mg/L)	Temperature (C)
Tank 1	8.27	8.4	25.4
Tank 2	8.21	8.3	25.43
Tank 3	8.15	8.2	25.48
Tank 4	8.23	8	23.32

Fish Behavior:
When we initially added fish to tanks we observed very little to no movement. After about 5-10 min fish began to move around. After 30 min we saw fish in groups of 3-4 move very slowly through riffles in tanks 4 to 3. Four would move halfway across, 3 would retreat, and only one would make it all the way through. Sharron predicted that the bigger minnows were pregnant females and interestingly enough we observed that they would stay closer to the floor of the tanks.

As we suspected, tank number 1, which has the bubbler hose, has the highest DO concentration decreasing in tanks 2, 3, then 4. pH was all over the place- no consistency. Tank 4, which has the pump motor seemed to have the lowest temperature. We turned off pump over our 4th of July break (a total of 36 hrs.) and took the following readings:

Thursday- 9:30am

	pH	DO (mg/L)	Temperature (C)
Tank 1	8	7	20.32
Tank 2	8	7.4	20.31
Tank 3	8	7.6	20.31
Tank 4	8	7.4	20.3

We observed that tank 3 has the highest concentration of plant matter and also higher DO. We suspect these are directly linked. Lori noted that lights were off during this period so photosynthesis would have decreased (although experiments show room lights have little influence on photosynthesis; the greatest contributor to photosynthesis is our sun) but cell respiration would have increased. We also observed tank 4 has the highest number of minnows. This again would yield a lower DO although minnows can gulp up air from the surface when exposed to harsh conditions.
Our next step will be to  measure again once the pump and bubbler have been on for two hours to compare data.

11:30am

	pH	DO (mg/L)	Temperature (C)
Tank 1	7.86	7.8	20.1
Tank 2	7.9	7.2	20.14
Tank 3	7.9	7.7	20.09
Tank 4	7.9	7.3	20.05

As expected after running the pump for 2 hrs. DO levels rose in a couple of the tanks. Tank 1, which has bubbler, rose significantly +.8. Tank 2, -.2. Tank 3, +.1. And Tank 4, -.1. No consistency here. I think what’s happening is that fish are migrating from tank to tank which fluctuates DO levels. Also, Spark probes might not be giving accurate data.

2:30pm

	pH	DO (mg/L)	Temperature (C)
Tank 1	8.07	7.5	20.12
Tank 2	8.03	7.4	20.07
Tank 3	8.03	7.1	20.07
Tank 4	8	7.7	20.08

Another set of data with varying numbers- no consistency. My next thought is volume of water affecting concentration of DO.

Week 4 Day 2

This morning we started out getting some things organized for our paper and pounding out some research. After that we went to two seminars. One was on robotic vision and that was not especially applicable to what we were working on. The first one, though, was explaining how you can use a UAV quadcopter as a tool in environmental surveys and research. Super cool. Also, if it wasn't for the FAA laws banning UAVs from commercial transactions this thing would make an awesome taco-copter.

I totally want one. After that we ran water through our artificial stream until it ran clear and then drained it as best we could. Then I situated the plants into the gravel and we filled it again. We treated the water and let it run for fifteen minutes. Once that was done Lori caught 15 fish and put them into tank one and then another 15 for tank 4. The thought there was we could see if the traveled upstream from tank 4 and see if they went down stream from tank one.

At first it didn't look like they were going to move much. We had one wash down the riffle from tank 1 to tank 2 right away and then another about a minute after. Then... nothing. They all went as deep as they could in their tank and stayed put. After a couple of hours, though, they started migrating. They will stay in one tank for a while and then one will get brave and head into a riffle. As soon as one does it four or five others will follow.

Once the artificial stream was in good shape we took another look at the circuit that Yixin had been perfecting. It now works exactly the way we want it to but it has gotten much more complex.

We are going to have to make four more of these bad boys so I sat down with Yixin and we started putting together the power controller for the sensor clusters. This is a lot more complicated then I expected and started out with Yixin making me wind coil for our DC transformers. Each transformer has two coils. The inner coil is wound 50 times with copper wire and the outer coil has 102. I made two of those today. I still have six more to go. After those were done we started laying out the circuit. Once I got a power controller set up completely on one of the boards we flipped it and Yixin told me to start soldering. I had a mild panic attack. Jennifer noticed and we started a soldering 101 refresher course. I made a couple of decent lines before I started screwing up. After that Joe jumped in and we started taking turns. By the time I stopped for the afternoon I was able to make two parallel tracks six spaces long with no bleed over or yellowing and Joe was getting close. After that we started talking about simple motors since we had copper wire laying around and I showed them one I made with my physics students.

While I was doing the electronics part, Lori and Joe were working with Dr. Hoeinghaus on the sensors, including setting up a YSI and giving him a run down on the artificial stream.