Vitz proveme wrong

[Anonymous]

2nd best thread, ever.

 

[Anonymous]

2nd best thread, ever.

thanks.

I guess I'll have to give them the answer some day :lol:

 

[Anonymous]

2nd best thread, ever.

thanks.

I guess I'll have to give them the answer some day :lol:

we're not holding our breath, i assure you :lol:


i'm still trying to figure out what the question is :?

 

[hawaiiguy]

beaslbob,
I'm really trying to figure out what's going on here (besides bickering)! While your claims seem wonderful, I'm with Vitz on this one so far. I'd like to understand what you are trying to say, though. It's just a matter of not understanding the point you are trying to make. Could you re-word it some other way and explain the simple math problem more clearly? Thanks!

 

[Anonymous]

beaslbob,
I'm really trying to figure out what's going on here (besides bickering)! While your claims seem wonderful, I'm with Vitz on this one so far. I'd like to understand what you are trying to say, though. It's just a matter of not understanding the point you are trying to make. Could you re-word it some other way and explain the simple math problem more clearly? Thanks!

The reason for this thread is the constant flames vitz and others give me on the effectivensess of water changes. with no analytical analysis at all. Any newbie coming into this hobby is told as the very first thing you must do 10% weekly water changes or 30% monthly water changes.

So lets actually analyze that method. Lets consider water changes and only water changes with a changing aquarium and see exactly how effective they are. That way we can gain some understanding of how effective they are compared to other things that are going on in the system. Of course the analysis should apply to any old thing, that is changing, and the analysis should be non-dimensional to apply to any size tank. And consider that the end result is not just intermediate values. The end result is when there are no changes from water change to water change.

Therefore consider these conditions:

1) consider water changes and only water changes.

2) That a given parameter must be maintained to less that 10 times the daily change. ****

3) replacement water has the ideal parameter

4) The parameter changes at 1/day (ppm, mg/L what ever unit).

5) water changes are conducted at 1%/day or multiples (10%/10 days, 20%/20 days, 30%/30days...... 100%/100days).

6) The system has been running that schedule sufficiently long that no further changes are be measured immediately before each water change.

(from the original)

Answer these questions:

1) What is value of that parameter immediately before water changes?

2) What is required to maintain that parameter within the desired 10 time the daily change through water changes? ****

3)How does that compair to ozboy's 3 month experience with 0 ammonia/nitrItes/nitrates?

And just to get the process started and as a huge hint:

Just to give you a hint try solving the above with the case of 100% water changes. Then see if you can solve the 50% case.

So there you go. Try to figure out what the value of something increasing a 1 per day is after 100 days. And what the value is after a 100% water change. And do that for another 100 days another water change and so on until the value right before the water change is the same as the value before the previous water change.

Then try to figure out why the values are not changing. And attempt to met those conditions for 50%. From then on you will find out something amazing. And immediately be able to answer all possible water change schedules including a constant flow through the tank equal to 1%/day water change.

then try to figure out what you must to to insure the parameter never goes over 10.

And then compare that to ozboy's experience.

And in that way you can get a handle on just exactly how effective water changes are.

But first you actually have to run some numbers. And not just parrot the 10%/week,30%/month, calcium will be maintained by water changes, etc ideas.

 

[Anonymous]

The reason for this thread is the constant flames vitz and others give me on the effectivensess of water changes. with no analytical analysis at all

Hey, meathead!

http://www.reefs.org/library/article/t_brightbill_wc.html

This whole article *IS* analytical analysis!

Peace,

Chip

 

[Anonymous]

The reason for this thread is the constant flames vitz and others give me on the effectivensess of water changes. with no analytical analysis at all

Hey, meathead!

http://www.reefs.org/library/article/t_brightbill_wc.html

This whole article *IS* analytical analysis!

Peace,

Chip

'zactly!! :wink: 8)

 

[Anonymous]

just please 'scuse beasle...

he rode to the lfs on the short bus :lol:


he doesn't even see where the problems are with his own 'math' assumptions :wink:

 

[Anonymous]

I will ignore any answer which does not directly respond to the question posted.

So there you go. Try to figure out what the value of something increasing a 1 per day is after 100 days. And what the value is after a 100% water change. And do that for another 100 days another water change and so on until the value right before the water change is the same as the value before the previous water change.

 

[Anonymous]

Try to figure out what the value of something increasing a 1 per day is after 100 days

i don't think anyone understands what that actually means :idea:

most likely because it doesn't mean anything ?

do you mean if you have 20 ppm of something and it increases at the rate of an additional 1ppm daily?

do you mean if you have 0 amount and it increases daily at 1ppm/day ?

do you mean by 1% a day ?


assuming that's what you mean, why do you even think that changes of anything are constant and linear over any unit of time in an aquarium?

 

[Anonymous]

don't make it too hard.

the increase is 1 per day as stated. not 1%

The water used has the ideal value.


Or you could have assumed that you have done sufficient water changes with the ideal parameter that the value just before each water change is the same. As stated in the conditions and as prediced by the article you referenced.

either way the water starts out at some ideal value and increases at 1 per day. And go from there

20ppm with a 1ppm daily is a specific example of that. Providing 20ppm is the value you consider optimal. And the replacement water also has 20ppm. So you can run with those values. the answer you get should apply to all values of whatever is optimal and in the replacement water.

 

[Anonymous]

in that case....


all of the answers you asked for are in that article i linked for you written by troy brightbill....


what didn't you understand ?

 

[Anonymous]

Ok then you should have absolutely no problem answering the questions.

 

[Anonymous]

i don't need to-the article did

 

[Anonymous]

i don't need to-the article did

Then you should be able to quote that article.

The problem is the article does not answer the problem.

The graphs shown either do not have an increase or decrease or do not carry out the problem to where the parameter change before the water change is constant.

 

[Anonymous]

i don't need to-the article did

Then you should be able to quote that article.

The problem is the article does not answer the problem.

The graphs shown either do not have an increase or decrease or do not carry out the problem to where the parameter change before the water change is constant.

then you need to take the short bus back to grade school, and take remedial math :lol:

that article addresses ALL math related to water changes, percentages, and diminishing returns-you just can't understand it :wink:


i'l bet you haven't looked at it, and i won't quote it, i've already linked it for you


spend a few days with it, and try to figure it out












if you like, i'll just say you're right, and i'm wrong, so then maybe you'll stop with your foolishness

by the way, can you post a picture of your tank(s) again, so we can see the results of your 'math' and maintenance philosophy you subscribe to? I'd love to see the results of your claims :lol:

 

[Anonymous]

Being as no one wants to answer the questions directly, just to review:

c1) consider water changes and only water changes.

c2) That a given parameter must be maintained to less that 10 times the daily change. ****

c3) replacement water has the ideal parameter

c4) The parameter changes at 1/day (PPM, mg/L what ever unit).

c5) water changes are conducted at 1%/day or multiples (10%/10 days, 20%/20 days, 30%/30days...... 100%/100days).

c6) The system has been running that schedule sufficiently long that no further changes are be measured immediately before each water change.

Questions to be answered.

q1) What is value of that parameter immediately before water changes?

q2) What is required to maintain that parameter within the desired 10 time the daily change through water changes? ****

q3) How does that compare to ozboy's 3 month experience with 0 ammonia/nitrites/nitrates?

Question one with the hint:

consider 100% water changes every 100 days (c5)

After 100 days the parameter has increased 100
After a 100% water change it is the ideal value in the replacement water
after another 100 days it is 100 above the ideal value
after a 100% water change is again is the ideal value of the replacement water.
And the cycle repeats meeting c6

Therefore, the answer to q1 is 100.


The reason that answer works is because:
1) there have been sufficient water changes that the tank has reached the ideal of the water change water plus the effects of the daily changes.
2) the parameter increase between changes has been completely removed by the water change.

Now consider 50% every 50 days. We conduct changes that the value after the water change is unmeasurably different from the value in the replacement water (C6). And again water change must remove the change between changes. After 50 days is a change of 50 and 50% of the water is changed. Therefore, the parameter will build up to 100 before the 50% water change removes all of the buildup.

Therefore what happens is:

Water_change:___days____before_change____after:
____100%_______100______100____________0
_____50%________50______100___________50
_____25%________25______100___________75
_____10%________10______100___________90
______1%_________1______100___________99
____1/1000%_____1/1000___100__________100-100*(1/1000)

So what happens is that under all possible water change schedules the parameter builds up to 100 times the daily change over the value in the replacement water. With larger water changes creating more variation in the parameter. But even a slow constant water change (flow) results in constant value 100 times the daily change over the value in the replacement water.

 

[Anonymous]

q2) What is required to maintain that parameter within the desired 10 time the daily change through water changes?

In order to limit the parameter to 10 times the daily change you must change the 100% every 10 days, or 50% every 5 days, 10% every day....

%______buildup_____before_____after.
100______10_________10________0
_50_______5_________10________5
_10_______1_________10________1

Again all schedules result in the same buildup just before the water change. But the greater amount of changes limit the buildup to 10.

To limit the build up to 1 you need 100% water changes per day. To maintain the parameter to the within 1 of the ideal condition you must conduct 100% of the water more often then once per day.

 

[Anonymous]

:lol:


:roll:



you're making critical faulty assumption(s)


do you know what they are ?

 

[Anonymous]

3)How does that compair to ozboy's 3 month experience with 0 ammonia/nitrItes/nitrates?

Water changes of 10%/10days would not have reduced the ammonia/nitrItes/nitrates in ozboy's tank.

Because oz established a system right from the start that prevented the increase in those things, water changes are unnecesary. the only thing that could have happened is that by "messing" with tank, the water changes could have increased the daily buildup,preventing the 0 values experienced.

The best setup is one that reduces the daily buildup hopefully to 0 or at least small enough they are unmeasurable for a few years. Water changes simply do not do that. 1 ppm pre day of nitrates IME is a small amount. We constantly have newbies posting they have 40-100ppm after a few months of operation dispite doing weekly 10% water changes.

What newbies and experts alike need to do and recognize is to establish plant life and bacteria to maintain the system. and not rely on water changes. Because even in tanks with 0 nitrates, none of the nitrates are being controlled by water changes.

Ditto for calcium, hardness, mag, alk and everything else.