let me know what u guys think…i know this is something we talked about before…
no doubt, high levels of co2 do cause ph in your tank to crash, even with great gas exchange on the surface of your water… if your exchanging co2 for co2 well… the headache thing is news to me and a nice little barometer to keep in mind!
correlation is not the correct word to use, i for get what is the correct one, just learned about it in AP stat… something that starts with A… o well (i should know this lol)
Interesting…
i believe correlation is determining whether two or more things, numerial or not, happen beyond just chance alone…all i remember is it has to fall between -1 and 1, lol…
so…i dunno if im right or not, lol…spelling bee time…“could you please use it in a sentence”
Does anyone believe there is a positive correlation between low pH and headaches? (that has to be right)lol…
ill never forget in like 5th grade i always used the word cornerstone, lol, that was like my fail safe smart word…but i was also using that in the wrong context, ha!
anyway, this makes me want to get this testing done in my office at work!! we have like 20 people in our little office at peak time.
after reading the comments on 3reef, a guy said he does an air change just like he does a water change, opens his door/window for a couple minutes to let in new air…i found that pretty interesting also
[quote=“longballz84, post:5, topic:2519”]
after reading the comments on 3reef, a guy said he does an air change just like he does a water change, opens his door/window for a couple minutes to let in new air…i found that pretty interesting also[/quote]
you should do this every day in the winter even for your own health, i do it, its cold for a few minutes then you can smell fresh air!
i do it, but i never thought about it benefiting the tank.
Correlation is how tight together your data points are. If the data points trend +x and +y then it will have a positive correlation. Correlation can be -1 to 1… -1 would mean its trening +x -y. You want to find the connection between low PH and headaches. Ill look in my stat notes tomorrow, but its not correlation. Its a— something or another. Ill post again tomorrow, when i have my stat notes. The way you find correlation is by finding the LSRL then complete a linear regression on it to find the r^2 and r values. R is the correlation. Which is how tight the points are to the LSRL. And R^2 is how well the data can be represented by graphing the y value on the x value. You can calculate the correlation without a calculator or minitab, but its a long equation and its to much of a hassle. So you don’t want the correlation. While that would verify your results accurate based on comparison to other points, it will not tell you if headaches are caused by low PH. Do you understand? ? It will be easier when i remember what the other word im looking for it. Correlation is often misused.
He meant contemplation.
The word is association. Now i remember. If you read the page it does an ok job explaining it. Correlation will only work if it is a linear result, like the weight of a piece of string per foot. It is always going to be constant. Your experiment will not be anywhere close to linear. It will surely be curved. You could transform the data through the Log of y and Log of x and many other transformations, and then it might be better to use the word correlation, but you want to find the association between Low PH and headaches not the correlation.
Does that make sense?..
i took AP Stat back in highschool, lol, im only 25 but i feel old now…
once i went to college…i used stat like twice, in my senior seminar class & economics…
Ya i hate it. I love math, hate analysis… But i took AP stat… lol easy but boring class… let me know when u get the data i analyze it… and see what we are working with… And ill be able to use it for extra credit in class lol
Good software makes it so you don’t need to learn off those fancy words 
FWIW High Co2 CAN lead to headaches, but I doubt as much you would notice it at 2500ppm. The supposed limit that will cause physiological effects its a TLV of 5000ppm (0.5%). The atmosphere contains around 350-450 ppm (0.04%). Now 10% will most certainly give you a headache and cause you to pass out and suffocate eventually.
Some other interesting facts, just cause.
CO2 is heaver than air so it will pool in low spots.
CO2 is the driver for human respiration, meaning CO2 is what causes you to breathe, not lack of oxygen.
The respiratory quotient is 0.85:1 for liters of CO2 produced per liter of O2 consumed.
If you are REALLY concerned I have equipment to test CO2 levels which I have checked against NIST traceable standards.
PS another reason to use kalk. Kalk = Calcium hydroxide an element that absorbs CO2 to create Calcium Carbonate or chalk.
Alls i know is that if i consume way too much red wine my stomach PH drops way below my comfort level and all kinds of bad stuff breaks loose.
Rook Owt!
Ya software like minitab but you still need to know some things
minitab
the best!
ha, i remember minitab…then it made me think of other programs i used i school i forgot about…
Oregan Trails, jesus…thats not even right…
yah, stat was a breeze for me too, ive always been good with numbers…def. take the test so u can get college credit for that AP course…i already had like 6 credit hours going into my freshman year of college…and i went to William Penn…lol…best public school in delaware (went to AI my freshman year and that was horrible)
Statistics is the one math class that everyone seems to always do well in.