Green Water Experiment

[urbanfarmer]

Has anyone tried this? Plenty of research on the topic, but I don't have a microbiology lab nor is my microscope even unpacked from the recent move...

Definitely a GREAT VALUE...


Green phytoplankton ready to be plundered...


Tank shot, basic setup 1x 100 Watt 6500K CFL light (also great value, LOL)


Another tank shot...


Tilapia will worship this like it was God...


Ammonia and Nitrite THROUGH THE PROVERBIAL ROOF!!!

(Nitrite LEFT | Total Ammoniacal Nitrogen RIGHT)

CONSIDERATIONS
Well, I am planning to let the green water sit overnight before adding any fish. I assumed there might be a high level of ammonia and nitrite in the water because the culture tank has been sitting in the dark for several days. If I leave the light on while letting it sit, it should absorb a good bit of the toxins and keep the water oxygenated so the bacteria can continue to work. I added about 4 gallons of concentrated green water and diluted with about 3 more gallons of dechlorinated water. I'm not sure if there is a diminishing return on algae growth as the concentration saturated per unit volume, but I assumed yes. I believe the water will become more saturated with algae overnight and I will test the water quality again prior to adding fish.

EXPERIMENT DESIGN
The experiment will be quite simple. I will have 2x 10 gallon tanks stocked with the same amount of water and the same amount of Blue Tilapia (Oreochromis aureus) fingerlings. I currently have 50x 1.5" Tilapia fingerlings and I will divide them between the 2 tanks. The green water tank is shown above and the other tank will simply be filled with dechlorinated tap water. The temperature will be maintained at 86 degrees Fahrenheit in both tanks via submersible aquarium heaters. The green water tank will not have any aeration added unless it is determined that the fish require a higher level of dissolved oxygen (if the majority of fish are observed at the surface due to low dissolved oxygen). I would prefer to simulate a low-tech, low maintenance situation for the green water tank.

I should weigh the Tilapia fingerlings to have roughly the same starting biomass in both tanks, but again, all my stuff is packed up so I will eyeball it.

The fish will be fed the same amount of high protein AquaMax 300 (ground up) per feeding. I would like to have a strict regime of feeding at specified times and quantities, but I'm going to eyeball it and feed whenever I can. This simulates the hobbyist situation more realistically anyway, but will be an added variable to consider albeit controlled via the control group.

ACKNOWLEDGEMENTS
Thank you davidstcldfl for providing the fish food.



...................................FEEDBACK? COMMENTS? SUGGESTIONS?

[JCO]

OH, so you didn't fill the jugs yourself...!

Don't let me bug you, I await your conclusions.

[urbanfarmer]

OH, I see what you did there... actually, I have some of those too...

I should have taken a picture with 1 of each!!!

[cedarswamp]

What is your hypothesis

[urbanfarmer]

What is your hypothesis

Observational Experiments

What are they?
An observational experiment is an experiment that students perform when they are investigating
a new phenomenon. Thus, they do not make predictions or have expectations about
its outcome. Students need to collect data, analyze them and find a pattern in the data.
They then need to explain the reasons for the pattern (if applicable), and/or construct a
qualitative or quantitative relationship.

Why do you want to use them?
Observational experiments have the following desirable features:

• • Concrete experiences
  These experiments provide concrete experiences as part of the learning cycle.
  • Open-mindedness
  Students learn to learn to approach data without knowing whether they are right or
  wrong.
  • Decision-making
  Students learn to make decisions about representing data, considering outliers, deciding
  what pattern they want to look for.
  • Epistemic cognition
  Students learn to deal with situations when there is no right answer. They learn how
  to choose a productive way to investigate complex phenomena.
  • Real data
  Students learn to deal with the complexities of real data.

How and where do you use them?
Observational experiments can be used in the following contexts:

• • In a lecture while developing ideas in a new topic.
  The instructor performs the experiment, students record data, decide what variables
  are important, and try to find patterns in the data by plotting graphs.
  • In the lecture, laboratory or recitation/workshop.
  The data from such experiments (performed by someone else) are provided. Students
  analyze them and look for patterns.
  • In the lecture, laboratory or recitation/workshop.
  The data and analysis are provided. Students construct explanations for the trends
  in the data.
  • In the laboratory. Students perform these experiments in the lab (before learning
  about them in lecture), collect and analyze data, find patterns, and construct explanations
  or mathematical relationships to describe the patterns.
  • As a homework problem. Data for an experiment are provided and students are asked
  to analyze the data and find patterns in them.

What are some types
Observational experiments can be used to introduce any new area of physics. They can be
either qualitative or quantitative. As described in the previous section, some or all parts
of an observational experiment can be used for example, students can collect and analyze
data, and/or find patterns, and/or construct explanations.


In my case, I am conducting a qualitative observational experiment...

CHA CHA CHA

There are research studies out there showing that green water pond culture supplemented with commercial feed will grow equal to or better fish mass per unit time than fish grown on just commercial feed. I have also read that very young tilapia are very efficient at feeding off phytoplankton, but when they grow the growth they gain is minimal compared to when they were young. I really have no aim with my experiment besides taking pictures and posting it on the forum!

[urbanfarmer]

UPDATE: 5/15/2011 18:00:00

Total Ammoniacal Nitrogen
still over 8.0 PPM (It's probably 40 PPM)

Nitrite
still over 5.0 PPM

Next Action
I will continue waiting until the levels drop to something safe to begin...


UPDATE: 5/16/2011 23:00:00

Total Ammoniacal Nitrogen
still over 8.0 PPM (color is not as DEEP, it's coming down now)

Nitrite
still over 5.0 PPM (this will probably come down a day or so after the ammonia)

Next Action
Still waiting for levels to drop...

[drdreww]

Can't wait 2 see how this all turns out. I will buy the book when you write it lol

[keith_r]

i'll be interested in following your data results, i'm thinking about something similar after much pond reading, except i want to start with the green water, add rotifers/daphnia, then add minnows and crays, then add my "target" fish..

[cedarswamp]

UPDATE: 5/15/2011 18:00:00

Total Ammoniacal Nitrogen
still over 8.0 PPM (It's probably 40 PPM)

Nitrite
still over 5.0 PPM

Next Action
I will continue waiting until the levels drop to something safe to begin...

In an "observational experiment" should you be making the assumption that the levels will drop to something safe or that they're unsafe to begin with?

[urbanfarmer]

In an "observational experiment" should you be making the assumption that the levels will drop to something safe or that they're unsafe to begin with?

I'm "waiting" for them to drop so I can start the experiment. Sorry for being unclear