beaslbob's water change analysis

beaslbob

Well-Known Member
At my request and promise to behave, the powers that be have restored my posting here.
For those who are fortunate to have missed the past, I have had various FW planted tanks and simple FO marine tanks since 1979. I still have my 55g which has had fish and soft corals for 3-5 years or so. I do not have any success with sps corals so I would seek advice from others for that.
I notice that not too many active posters remain from five years ago so I thought I would reintroduce myself with a discussion of water changes just for your consideration.
Fortunately, water changes are something that can be analyzed with math given a few assumptions. As opposed to more emotional arguments like how would you like to live in a bathtub with no water changes or water changes replace trace elements.
For the following analysis I am assuming something is in the replacement water. So let's call that “something”. Gee how original.
And something in the water is at a certain concentration of galloping elephants.
So this could be anything of any units of concentration. But let's also assume that galloping elephants is a linear measure unlike pH.
So you have a tank with some initial galloping elephants of something. And every so often you do a 10% water change. So after the first change you have 9/10s of the initial remaining. Second is 9/10s of that for 9/10*(9/10). the third (9/10)*(9/10)*(9/10) and so on. So that after sufficient water changes you have unmeasurable initial galloping elephants and the tank totally reflects the galloping elephants of the replacement water.
Simple. And what you usually hear here, at LFSs, in normal conversations and so on.
But now also assume that the tank has a constant change in something so that each day you have more or less galloping elephants. To analyze this case assume the replacement water has no galloping elephants. And to make analysis easier assume water changes are conducted at the same level and interval.
How much something is in the tank just before each water change after enough water changes have been conducted that we cannot measure the difference? In order for that to be true:
The amount of (between water change) change in something must be removed by the water change.
So if you do say 10% water changes, something must be 10 times the change. The water change then lowers the change to 9 times and something builds up again to 10 times just before the next change. 20% 5 times to 4 to 5. 33% 3 times to 2 to 3. etc. Mathematically:
just before water change=(change between water changes)/(fraction of water changes)
If you allow for some of something in the replacement water you combine the two effects:
just before water change=(change between water changes)/(fraction of water changes)+replacement water
If you “tie” the amount of water changes to the water change some interesting (to me anyway) results happen. Like 1%/day, 10%/10 days and so on. In that case:
Just before water change=(daily change*days between water changes)/(fraction of water changes)+replacement water.
Under those assumptions the following occurs:
days_____change__before_after___next
100______100%___100____0_____100
50_______50%_____100__50___100
33_______33%_____100__67___100
20_______20%_____100__80___100
10_______10%_____100__90___100
5_________5%_____100__95___100
1_________1%_____100__99___100
.5________.5%_____100_99.5__100
The limit of a continuous change at the rate of 1%/day you have a continuous 100 galloping elephants.
And to all those figures you add in whatever the concentration is in the replacement water. Both the before and after values are increased by whatever is in the replacement.
 

beaslbob

Well-Known Member
Now if we step back and look at:
just before water change=(change between changes)/(fraction of water changes)+replacement water
We can start thinking about what is important. To limit the build up to the daily change we have to do one of two things:
1)conduct 100% daily water change
or
2)get the change between changes as close to 0 as possible.
The first case in not practicable but the second is realizable.
So to me the key is reaching the second case.
IME it is not unusual to have 1ppm daily increase or 1ppm daily consumption of calcium.
If you have been running your tank for a few weeks/months and have 100ppm nitrates the reason is not because you have been conducting sufficient water changes but rather because the tank setup is not consuming nitrates as they are being generated. If you have 350ppm calcium with replacement water of 450ppm again it is not because your water changes are ineffective, the tank is just not balanced out and has a net consumption of calcium.
So aerobic bacteria takes care of ammonia/nitrItes. Plant life and anaerobic bacteria consume nitrates. Plant life consume phosphates and carbon dioxide. Plant life and anaerobic bacteria return carbonates as they consume nitrates. Calcium/carbonate(alk)/magnesium have to be dosed to keep those values up.
Which is why all my tanks have had no water changes since first setup. The 55g has been that way since 2002 , 29g since 2006. On the Fw side I have a 10g running since 2002 with descendants of the original cycle trio. I have not touched the glass inside for over 2 years and there is virtually no algae on the glass.
So it just makes sense to me to recycle the nutrients into fish food with plant life.
I know there have been several threads on water changes here so now I will await your response.
And with my more mature posting method

[hr]
listening.
My .02
 

flower

Well-Known Member

Never heard of you. But HELLO!
I have a friend who has not done a water change in 26 years. His reef looks great. I on the other hand, am just not that brave.
If your tank is healthy, and you are happy with the way it looks, what difference will it make? Do what makes you happy.
How about some pictures of your tank?
 

reefkprz

Active Member
2004..... wow bob what did you do? actually better left unsaid.
my question is how do I dose galloping elephants and how much is the test kit?
 

reefkprz

Active Member
Originally Posted by beaslbob
http:///forum/post/3183748
I have not touched the glass inside for over 2 years and there is virtually no algae on the glass.
view through the come and go coraline must be awefully spotty

just yanking your chain. my martini thought it was a good idea.
 

bang guy

Moderator
Originally Posted by beaslbob
http:///forum/post/3183747
Under those assumptions the following occurs:
days_____change__before_after___next
100______100%___100____0_____100
50_______50%_____100__50___100
33_______33%_____100__67___100
20_______20%_____100__80___100
10_______10%_____100__90___100
5_________5%_____100__95___100
1_________1%_____100__99___100
.5________.5%_____100_99.5__100
The limit of a continuous change at the rate of 1%/day you have a continuous 100 galloping elephants.
For the given assumption it's quite clear that this method of water change isn't ever going to reduce the Elephant concentration long term.
In order to reduce the Elephants we'll have to remove the Galloping Elephants faster that they reproduce. If we removed 25% of them every 7 days the long term effect is a bit different:
Day__Before__After__Next
0____100____75____82
7____82_____62____69
14___69_____52____59
21___59_____44____51
28___38_____29____36
So, after only a month we have the Elephants down to a level, long term, where they're not continually stomping down the village and causing other michief.
 

beaslbob

Well-Known Member
Originally Posted by Flower
http:///forum/post/3183754

Never heard of you. But HELLO!
Thanks
I have a friend who has not done a water change in 26 years. His reef looks great. I on the other hand, am just not that brave.
If your tank is healthy, and you are happy with the way it looks, what difference will it make? Do what makes you happy.
How about some pictures of your tank?
I'll try to get a picture of the 29g. Meanwhile I think an excellent picture would be one of your friend's tank.
my .02
 

beaslbob

Well-Known Member
Originally Posted by beaslbob
Originally Posted by Bang Guy
http:///forum/post/3183780
Welcome back Bob

Algae returns Carbonate?

Or bicarbonates.
It was an article by dr homes-farley which I have lost reference/link too. Alkalinity or pH or something in reef tanks.
The aerobic bacteria release an h+ in the both the ammonia to nitrItes and nitrItes to nitrates process. Which "uses up" alk. But both anaerobic consumption of nitrates to n2 gass, and algae consumption (to plant tissue) return 2 carbonates (or bicarbonates) to the system.
The article gave the chemical reactions plus had an interesting discussion on the effects of water changes the remove nitrates.
This would also explain the pH drop while cycling with aerobic bacteria, then the rise in pH after the process has finished.
Perhaps someone can find the article. The site where I referenced it is off line the last week or so.
my .02

edit
Woopsies my original post is above. Below is my addition which I originally wanted to be a new post.
Found the article.
It was in Reefkeeping titled "When Do Calcium and Alkalinity Demand Not Exactly Balance?" by Dr Randy Holmes-Farley.
Originally Posted by article by Dr Randy holmes-Farley

One of the best known chemical cycles in aquaria is the nitrogen cycle. In it, ammonia excreted by fish and other organisms is converted into nitrate. This conversion produces acid, H+ (or uses alkalinity depending on how one chooses to look at it), as shown in equation 1:
(1) NH3 + 2O2 � NO3- + H+ + H2O
For each ammonia molecule converted into nitrate, one hydrogen ion (H+) is produced. If nitrate is allowed to accumulate to 50 ppm, the addition of this acid will deplete 0.8 meq/L (2.3 dKH) of alkalinity.
However, the news is not all bad. When this nitrate proceeds further along the nitrogen cycle, depleted alkalinity is returned in exactly the amount lost. For example, if the nitrate is allowed to be converted into N2 in a sand bed, one of the products is bicarbonate, as shown in equation 2 (below) for the breakdown of glucose and nitrate under typical anoxic conditions as might happen in a deep sand bed:
(2) 4NO3- + 5/6 C6H12O6 (glucose) + 4H2O � 2 N2 + 7H2O + 4HCO3- + CO2
In equation 2 we see that exactly one bicarbonate ion is produced for each nitrate ion consumed. Consequently, the alkalinity gain is 0.8 meq/L (2.3 dKH) for every 50 ppm of nitrate consumed.
Likewise, equation 3 (below) shows the uptake of nitrate and CO2 into macroalgae to form typical organic molecules:
(3) 122 CO2 + 122 H2O + 16 NO3- � C106H260O106N16 + 138 O2 + 16 HCO3-
Again, one bicarbonate ion is produced for each nitrate ion consumed.
A further discussion on water changes:
Originally Posted by article by Dr. Randy Holmes-Farley
If, for example, nitrate averages 50 ppm at each water change, then over the course of a year with 10 water changes of 20% each, the alkalinity will be depleted by 1.6 meq/L (4.5 dKH) over the course of that entire time period. This process is one of the primary reasons that fish-only aquaria that often export nitrate in water changes need occasional buffer additions to replace that depleted alkalinity
Of course if the algae is consuming (bi)carbonates like corraline or halimedia you further deplete the carbonates.
my .02
 

beaslbob

Well-Known Member
Originally Posted by reefkprZ
http:///forum/post/3183907
2004..... wow bob what did you do? actually better left unsaid.
my question is how do I dose galloping elephants and how much is the test kit?
There is not test for galloping elephants as that is the units of concentration of something.
You can get the beaslbob test kit for something calbrated in galloping elephants and the dosing syringe (calibrated in galloping elephants) at www dot beaslbob dot org for $50,000 in small bills.
Fortunately you can find something at you local non aquarium stores.
I understand that site does not have a good reputation for being responsive though.
my .02
 

beaslbob

Well-Known Member
Originally Posted by reefkprZ
http:///forum/post/3183910
view through the come and go coraline must be awefully spotty

just yanking your chain. my martini thought it was a good idea.

It's a FW tank.
pass the martuni please.
 

beaslbob

Well-Known Member
Originally Posted by Bang Guy
http:///forum/post/3184004
For the given assumption it's quite clear that this method of water change isn't ever going to reduce the Elephant concentration long term.
In order to reduce the Elephants we'll have to remove the Galloping Elephants faster that they reproduce. If we removed 25% of them every 7 days the long term effect is a bit different:
Day__Before__After__Next
0____100____75____82
7____82_____62____69
14___69_____52____59
21___59_____44____51
28___38_____29____36
So, after only a month we have the Elephants down to a level, long term, where they're not continually stomping down the village and causing other michief.

Well let's test my little equation. 25% water change ever 7 days zero galloping elephants of something and a 1 galloping elephants/day increase of something
buildup between water changes is 7 galloping elephanats. 1/4 of water changes with 0 added. Final just before galloping elephants is 7*1/(1/4)=28. Which is where your analysis will wind up at. The reason it concentration is decreasing is because we started above the final point.
 

beaslbob

Well-Known Member
Originally Posted by Bang Guy
http:///forum/post/3184004
...
So, after only a month we have the Elephants down to a level, long term, where they're not continually stomping down the village and causing other michief.

Thanks Bang and glad you are still here.
beaslbob org is pleased to announce the availablility of the super secret reef safe additive for saltwater tanks.
There are two kinds of elephants, the dangerous free one as Bang stated and the ;other is the safe "locked" version. Beaslbob has developed a method to lock up the free elephants and prevent village losses.
One of the problems is that normal elephant test kits are "fooled" because they measure to total of both the free and locked elephants because it sets free the locked elephants then counts all the elephants present.
In order to prevent that beaslbob has developed a test kit that counts both the free and total elephants. So you can judge how much to dose.
We have feed back the product also controls ivory and other end products of the elephant cycle. But the product was not tested or designed for that use so user beware.
And the plus version of the product controls the gas form as well the solid elephants.
All of which is again available at the beaslbob web site for $50,000 in small bills.
 

spanko

Active Member
Originally Posted by beaslbob
http:///forum/post/3184511
Thanks Bang and glad you are still here.
beaslbob org is pleased to announce the availablility of the super secret reef safe additive for saltwater tanks.
There are two kinds of elephants, the dangerous free one as Bang stated but the safe "locked" version. Beaslbob has developed a method to lock up the free elephants and prevent village losses.
One of the problems is that normal elephant test kits are "fooled" because the measure to total of both the free and locked elephants because it sets free the locked elephants then counts all the elephants present.
In order to prevent that beaslbob has developed a test kit that counts both the free and total elaphants. So you can judge how much to dose.
We have feed back the product also controls ivory and other end products of the elephant cycle. But the product was not tested or designed for that use to user beware.
And the plus version of the product controls the gas form as well the solid elephants.
All of which is again available at the beaslbob web wite for $50,000 in small bills.

Also available for Blu-ray in February 2010.
 

bang guy

Moderator
Originally Posted by beaslbob
http:///forum/post/3184504
Well let's test my little equation. 25% water change ever 7 days zero galloping elephants of something and a 1 galloping elephatg/day increase of something
buildup between water changes is 7 galloping elephanats. 1/4 of water changes with 0 added. Final just before galloping elephants is 7*1/(1/4)=28. Which is where you analysis will wind up at. The reason it concentration is decreasing is because we started above the final point.

Yes, there is a final terminator. A reason why water changes are only one tool in the toolbox for reducing galloping elephants. No single tool is perfect in all situations which is why it's a good idea to consider all tools in the box and utilize them in the manner best fitting for your specific application.
 

beaslbob

Well-Known Member
Originally Posted by Bang Guy
http:///forum/post/3184567
Yes, there is a final terminator. A reason why water changes are only one tool in the toolbox for reducing galloping elephants. No single tool is perfect in all situations which is why it's a good idea to consider all tools in the box and utilize them in the manner best fitting for your specific application.

+1
 

renogaw

Active Member
wow, i was like, beaslbob's posts are getting bumped...Good to see you're back. you've helped me in the past via email and it will be good to get your views back here :)
 

beaslbob

Well-Known Member
Originally Posted by renogaw
http:///forum/post/3186944
wow, i was like, beaslbob's posts are getting bumped...Good to see you're back. you've helped me in the past via email and it will be good to get your views back here :)
Thanks. Glad I was able to help.
 
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