Good Science is Repeatable

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CHOMPERS

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Apr 28, 2006
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A week or two ago, Dodgefreak published some results of his nitrate tests in his planted tank. It was interesting results and I will post a link to his thread if I can find it (anyone feel free to help me out). I ran out of ammonia absorber for my turtle tank so I got to thinking that this would be a good time for another experiment. One thing I forgot was to run a control batch. You know what happens there (not much) but the results were interesting still. I had planned to map the consumption of nitrates through the course of a week and then plot the results on a chart. My interest is whether nitrate consumption is linear or a decreasing exponential function. At this point, it is not derivable but the results are very interesting as you will see.

The source water is as follows:
Ammonia .5
Nitrites .5
Nitrates 15
pH 6.6

The experiment began at 9:00pm 10-2-06. The results were tested 27 hours later at 12:00am 10-4-06. The first test vessel is 1.6 gallons of source water with densely packed aquatic plants. They were exposed to approximately 12 hours of diffused sun light. The second test vessel is 1.6 gallons of source water with one sprig of phothos containing seven developed leaves and a root system that is 1.5 months old. It was exposed to 6.5 hours of artificial light split into two sessions of three hours and three and a half hours. The artificial light was supplied by two fluorescent aquarium/plant lights.

Aquatic plants after 27hrs with 12hrs of light:
Ammonia 0.0
Nitrites 1.0
Nitrates 5.0
pH 6.4

Sprig of phothos with 6.5hrs of light:
Ammonia 0.0
Nitrites .25
Nitrates aprox. zero
pH 6.6

These results were totally unexpected. I do not have a source of bad water right now but I will be generating some shortly so that I can repeat this experiment. I will try to eliminate the some of the variables. I will also run a control group.

Of course, the question of nitrate consumption being linear or exponential is still unanswered. If the aquatic plants tank is zero tomorrow, it will still be inconclusive. If there are testable nitrate levels it will, at best, suggest that nitrate consumption is exponential.
The more people that repeat this experiment, the better the empirical evidence will be. Maybe we can start to shed some of the internet myth that plagues our hobby.
 
CHOMPERS;530275; said:
My interest is whether nitrate consumption is linear or a decreasing exponential function.

As a function of what? time? temperature? biomass? original nitrates? other nutrients? Light intensity? Which ever you choose, the others have to be kept constant.

You also need to define "aquatic" plants. There is a huge difference between slow growers (Anubia nana) or fast growers (Elodea densa) and floating plants (Pistia stratiotes).

Good luck,
HarleyK
 
CHOMPERS;530275; said:
A week or two ago, Dodgefreak published some results of his nitrate tests in his planted tank. It was interesting results and I will post a link to his thread if I can find it (anyone feel free to help me out). I ran out of ammonia absorber for my turtle tank so I got to thinking that this would be a good time for another experiment. One thing I forgot was to run a control batch. You know what happens there (not much) but the results were interesting still. I had planned to map the consumption of nitrates through the course of a week and then plot the results on a chart. My interest is whether nitrate consumption is linear or a decreasing exponential function. At this point, it is not derivable but the results are very interesting as you will see.

The source water is as follows:
Ammonia .5
Nitrites .5
Nitrates 15
pH 6.6

The experiment began at 9:00pm 10-2-06. The results were tested 27 hours later at 12:00am 10-4-06. The first test vessel is 1.6 gallons of source water with densely packed aquatic plants. They were exposed to approximately 12 hours of diffused sun light. The second test vessel is 1.6 gallons of source water with one sprig of phothos containing seven developed leaves and a root system that is 1.5 months old. It was exposed to 6.5 hours of artificial light split into two sessions of three hours and three and a half hours. The artificial light was supplied by two fluorescent aquarium/plant lights.

Aquatic plants after 27hrs with 12hrs of light:
Ammonia 0.0
Nitrites 1.0
Nitrates 5.0
pH 6.4

Sprig of phothos with 6.5hrs of light:
Ammonia 0.0
Nitrites .25
Nitrates aprox. zero
pH 6.6

These results were totally unexpected. I do not have a source of bad water right now but I will be generating some shortly so that I can repeat this experiment. I will try to eliminate the some of the variables. I will also run a control group.

Of course, the question of nitrate consumption being linear or exponential is still unanswered. If the aquatic plants tank is zero tomorrow, it will still be inconclusive. If there are testable nitrate levels it will, at best, suggest that nitrate consumption is exponential.
The more people that repeat this experiment, the better the empirical evidence will be. Maybe we can start to shed some of the internet myth that plagues our hobby.

you have way too many gaps and missing info in this experiment.

im reading jibberish here man :confused:

what you trying to do?, i understand it has to do with lowering nitrate
 
CHOMPERS The source water is as follows: Ammonia .5 Nitrites .5 Nitrates 15 pH 6.6 The experiment began at 9:00pm 10-2-06. The results were tested 27 hours later at 12:00am 10-4-06. The first test vessel is 1.6 gallons of source water with densely packed aquatic plants. They were exposed to approximately 12 hours of diffused sun light. The second test vessel is 1.6 gallons of source water with one sprig of phothos containing seven developed leaves and a root system that is 1.5 months old. It was exposed to 6.5 hours of artificial light split into two sessions of three hours and three and a half hours. The artificial light was supplied by two fluorescent aquarium/plant lights. Aquatic plants after 27hrs with 12hrs of light: Ammonia 0.0 Nitrites 1.0 Nitrates 5.0 pH 6.4 Sprig of phothos with 6.5hrs of light: Ammonia 0.0 Nitrites .25 Nitrates aprox. zero pH 6.6 QUOTE said:
Chompers me thinks your on to something here!

Interesting that the Pothos seemed to obliterate the nitrates and consume the ammonia (same as the aquatics) even though it had less light. This is not a surprise since terestrial plants can respirate more efficiently than their water logged cousins and generally have higher metabolisms.

I also notice that the nitrite level was reduced significantly compared to the aquatic plants. I wonder if the roots of your pothos are colonized by BB that can consume the nitrate and convert it to nitrate for the benefit of the pothos. Kind of a symbiotic relationship between BB and pothos. Habitat and oxygen(?) in exchange for nitrates. This has been demonstrated in some terestrial plants such as clover and peanuts as examples. But what is going on with the pH?

You may be on the virge of the next generation of biofiltration. I suggest developing a protocol for an experiment and getting volunteers like me to attempt to duplicate your results.............Anyone else want to play?
 
HarleyK;530568; said:
As a function of what? time? temperature? biomass? original nitrates? other nutrients? Light intensity? Which ever you choose, the others have to be kept constant.

You also need to define "aquatic" plants. There is a huge difference between slow growers (Anubia nana) or fast growers (Elodea densa) and floating plants (Pistia stratiotes).

Good luck,
HarleyK

Hi Harley,
Embarasingly, I do not know what types of plants that I have. They are the "you can't kill these no matter what you do" types of plants. I tried to give them the best possible conditions by giving them difused sunlight. I didn't intend to pit them in a competition against the pothos (after reading my writing, that is how it sounded). I had expected the aquatic plants to do better than they had. They are slow growers, which is why I wanted to give them the best possible conditions. Still they out performed my expectations. What really blew me away was the sprig of pothos with only seven leaves (and one still curled up). I didn't expect much performance out of it, but it turned out to be the one to steal the show. It is in a 30g frog terrarium and I didn't change any perameters from its daily routine.

The function that I was looking for was with respect to time. I was looking for evidence if the nitrate consumption is constant with respect to time or if it changed depending on concentration over the same course of time. That information will tell us if plant use is evenly benifficial across the board or if those with higher nitrate production would receive the most advantage from plants. With that in mind, you can see why I was relaxed in the different amounts of light, temperature, and other significant factors. I think it would be interesting to find out the consumption rate on a per species basis. I just don't think that I will have the time for that scale of a project. Maybe we have some biology students that need a dissertation topic :popcorn:
 
CHOMPERS;532510; said:
... They are the "you can't kill these no matter what you do" types of plants. ...

Ummm....plastic?

Ok so it isn't often that I get to quote myself.
 
HiGhTiMeZ;530933; said:
**** i did not understand ANYTHING!
damn im dumb! :screwy:

An education gained by osmosis is a free education. Ask away! When I was in highschool, I formed a theory based on that saying "You can't soar like an eagle if you are surrounded by turkeys"...I came up with the idea that if I surrounded myself with smart people and took challenging classes but didn't try, then I would absorb an education from my environment. I kinda wished that I gave a better effort though.

It is easier for me to design and run these experiments because I have the thought and goal in my head. I know what I want to do and get accomplished. Transfering those thoughts and the procedures to meaningful words for the reader takes a special tallent that I am still trying to develope.

Keep in mind that the two plants in the experiment were intended to be observed independently of the other and were not intended to be in competition with each other. The goal was to set both plants on their merry way and then test the water daily for a week or however long it took for them to consume the nitrates. Dodge freak did two tests one week apart, so that gave me the one week interval. I wanted to get readings in between those two readings to see what is actually going on in the nitrate consumption process.

ok, now ask away! :)
 
DeLgAdO;530959; said:
you have way too many gaps and missing info in this experiment.

im reading jibberish here man :confused:

what you trying to do?, i understand it has to do with lowering nitrate

Oh come on now. I know you are really smart and can read my jibberish. :D I wrote it either late at night or I was sleep deprived...or both. Hopefully the other two posts cleared up my mess. If not, just ask and I shall surely answer.
 
CHOMPERS;530275; said:
A week or two ago, Dodgefreak published some results of his nitrate tests in his planted tank... ... At this point, it is not derivable but the results are very interesting as you will see.
...

Ah yes, the jibberish... the translation:

I had some crappy water and decided to see how well plants consumed nitrates (and what ever else they may do to aquarium water). I had enough water to play with two sets of plants because they would probably consume the nitrates at different rates. I tested the water ahead of time so I would have something to compare any results to. After one day, I did the first test and way more nitrates were consumed than I had ever expected.
 
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