Refugiums

[lduncan]

Because adding water volume doesn't change anything to do with vacuuming sand!!! The two are totally independent.

Hence my saying earlier that you are bringing in factors totally unrelated to adding water volume, and trying to attribute their effects to added water volume.

It's just plain irrelevant.

Layton

[wasp]

Because adding water volume doesn't change anything to do with vacuuming sand!!! The two are totally independent.

Layton

I think I just heard the penny drop. It doesn't.

Vacuuming the sand will remove exactly the same amount of crud, even if you double the water volume.

Therefore you have the same crud being removed, but twice the water volume to dilute the rest.

Starting to see what happens in a real tank now?

[lduncan]

Oh God, i'm not going any further than this. I don't know how much longer I can go on with explaining this. Wasp, think rates of input/removal and what changes them, then think concentrations etc.

[puttputt]

thats twice you've said that layton

Go Wasp!!

[lduncan]

Think about it a bit more wasp...

[wasp]

Wasp, think rates of input/removal and what changes them, then think concentrations etc.

Exactly right Layton, that's what I just did. Now if you can think the same thing, you may be able to understand. Perhaps read my last post again, slowly.

i'm not going any further than this. I don't know how much longer I can go on with explaining this.

Seen you say that before once you know your wooped.

[lduncan]

No, when i'm done trying to explain things to people who don't make sense.

Layton

[wasp]

No, when i'm done trying to explain things to people who don't make sense.

Layton

Truth is, you got so upset because my post which showed where your argument falls over, made perfect sense. Here it is again, please explain where it does not make sense :lol:

I think I just heard the penny drop. It doesn't.

Vacuuming the sand will remove exactly the same amount of crud, even if you double the water volume.

Therefore you have the same crud being removed, but twice the water volume to dilute the rest.

Starting to see what happens in a real tank now?

Layton, I know it must be hard, being surrounded by idiots, but always loosing your arguments to them :lol:

But I'm really not trying to beat you to a pulp, just explaining things logically.

Just see it, as you have done in the past, as learning.

[puttputt]

I think i'll leave this one here.

i'm not going any further than this

[lduncan]

Truth is, you got so upset because my post which showed where your argument falls over, made perfect sense. Here it is again, please explain where it does not make sense :lol:

If I had more time, i'd persist with explaining, might do later in the week. But for now I don't have the time to burn.

But in the mean time keep thinking about it. Add a constant output to the model and see what happens. You might get a surprise.

Layton

[wasp]

If I had more time, i'd persist with explaining, might do later in the week.

Layton

I've heard that one before too, once you realised you were incorrect but won't admit it.

Seems some people would rather say anything than admit they're wrong! :lol:

[lduncan]

I'm saying think about it more.

Think about the processes going on, does a change in water volume effect them. And ultimately do these change the final outcome. IE does it result in lower concentrations of nutrients.

Layton

[wasp]

Oh. Thought you didn't have time :lol: :lol:

"Think about it more". Very non specific Layton. A total cop out when you have nothing concrete to say.

Reminds me of the Co2/pH debate, when even after Randy Holmes Farley told you you were wrong, you kept arguing anyway. :roll:

[lduncan]

I don't have time to step you through it at the moment.

As for me copping out with non-specifics, How about you get specific with these "other factors"? You've said that they effect the outcome, so show me HOW they do that.

Maybe you could tell me how you think the removal of waste from sand is affected by extra water volume?

Are you saying that the mass of waste removed is the same before and after extra water volume is added?

Are you saying that the mass of waste removed increases proportionally to the extra water volume added?

Are you saying that the mass of waste removed reduces inversely to the extra water volume added?

Or are you saying something entirely different?

Layton

[lduncan]

Reminds me of the Co2/pH debate, when even after Randy Holmes Farley told you you were wrong, you kept arguing anyway. :roll:

Oh, you mean that thread where you berated me for trying to find out something?:

http://www.fnzas.org.nz/fishroom/5-vt13 ... l?start=62

It wasn't arguing I was attempting to get a full understanding of something.

Layton

[wasp]

I don't have time to step you through it at the moment.Layton

But you keep coming back anyway

Seem to have plenty of time for argument, just none to disprove my point.

As for me copping out with non-specifics, How about you get specific with these "other factors"? You've said that they effect the outcome, so show me HOW they do that.Layton

Just done it :roll:

Maybe you could tell me how you think the removal of waste from sand is affected by extra water volume?Layton

It isn't. I've told you that heaps, perhaps read it slowly. "Removal of waste from sand is not affected by water volume".

Are you saying that the mass of waste removed is the same before and after extra water volume is added?Layton

No. I'm saying that depending on the processes involved, it may, or it may not.

[wasp]

It wasn't arguing I was attempting to get a full understanding of something.

Layton

[lduncan]

It isn't. I've told you that heaps, perhaps read it slowly. "Removal of waste from sand is not affected by water volume".

When you say that you are implying that if you increase the water volume, the export of waste from the sand is the same, are you not?

No. I'm saying that depending on the processes involved, it may, or it may not.

But I thought few sentences ago you said that extra water volume doesn't affect it? Can you clarify this a bit more?

Anyway taking what you said here, in the circumstances where you think it's not the same, what has caused it to change?

Layton

[wasp]

But I thought few sentences ago you said that extra water volume doesn't affect it? Can you clarify this a bit more?Layton

No as usual you will have misunderstood. Please show me which sentence you refer to and I will clarify for you, if this will help.

Anyway taking what you said here, in the circumstances where you think it's not the same, what has caused it to change?Layton

Don't know what you are talking about. Cause what to change?

[lduncan]

No as usual you will have misunderstood. Please show me which sentence you refer to and I will clarify for you, if this will help.

This one:

"Removal of waste from sand is not affected by water volume".

I take that to mean that water volume has absolutely no effect on removal of waste from sand, which directly implies that the removal of waste before and after adding more water volume is the same. Am I wrong? Then in the next breath you say that depending on the processes involved, it may, or it may not, be the same. Which is it?

Don't know what you are talking about. Cause what to change?

Well you said that depending on the processes involved, the mass of waste removed may, or may not be the same before and after extra water volume is added. I'm asking in the case where it is not the same, what has caused it to change?

Layton

[wasp]

This one:

I take that to mean that water volume has absolutely no effect on removal of waste from sand, which directly implies that the removal of waste before and after adding more water volume is the same. Am I wrong? Then in the next breath you say that depending on the processes involved, it may, or it may not, be the same. Which is it?Layton

Yes as I suspected, you have misunderstood, as usual, I suspect deliberately. In the first instance, I am referring to removal of waste from sand by vacuuming, which will be unnaffected by adding more water volume. In the second instance, or what you rather stupidly refer to as "the next breath", I say that "depending on the processes involved, it may, or it may not, be the same".

This was not "the next breath", let's at least be honest Layton. It was actually the answer to a different question, not about sand vacuuming. Trying to string stuff I said together & make it look like I said something else, is merely showing your desperation at having lost the argument.

Anyhow, "depending on the processes involved" means exactly that. It depends on the processes involved. The process may for example, be skimming, it may be dentrification, it may be vacuuming, whatever. Some of these processes are affected by water volume, some are not.

If you are still confused, read it slowly and think about it. it is all completely logical. May pay also for you to go back over the thread and have a look at what was actually said, so you will no longer be confused about what was the answer to what question, on what subject.

Well you said that depending on the processes involved, the mass of waste removed may, or may not be the same before and after extra water volume is added. I'm asking in the case where it is not the same, what has caused it to change?

Your question is poorly worded i am still not 100% sure what you are talking about. But if it is what i THINK you mean, see above

And Oh, Big IS Good

[lduncan]

Yes as I suspected, you have misunderstood, as usual. In the first instance, I am referring to removal of waste from sand by vacuuming, which will be unnaffected by adding more water volume. In the second instance, or what you rather stupidly refer to as "the next breath", I say that "depending on the processes involved, it may, or it may not, be the same".

This was not "the next breath, let's be honest Layton, it was actually the answer to a different question. trying to string stuff I said together & make it look like I said something else, is merely showing your desperation at having lost the argument.

Now I see why you said that, I was referring to the specifics of vacuuming sand before throughout. That's why I asked for clarification, there's no need for you to get presumptuous.

Anyhow, "depending on the processes involved" means exactly that. It depends on the processes involved. The process may for example, be skimming, it may be dentrification, it may be vacuuming, whatever. Some of these processes are affected by water volume, some are not.

If you are still confused, read it slowly and think about it. it is all completely logical.

Well then for starters you can ignore those processes which are not affected by water volume, as they don't affect the steady state outcome.

Focus on the "other factors" which may be affected by water volume. Then you have to look at how they are effected to see if they alter the steady state. Are there any factors that you think are dependent on water volume and will change the end result? What are they?

Your question is poorly worded i am still not 100% sure what you are talking about. But if it is what I THINK you mean, see above

Your explanation above has clarified this.

So now we can agree that vacuuming sand doesn't effect the final steady state result. And my claim that increasing water volume doesn't change nutrient concentrations in the steady state still stands.

Layton

[wasp]

Well then for starters you can ignore those processes which are not affected by water volume, as they don't affect the steady state outcome.

Layton

That's where you're wrong.

Check this -

Think about the processes going on, does a change in water volume effect them. And ultimately do these change the final outcome. IE does it result in lower concentrations of nutrients.

Layton

Isn't that what I've just run you through? You still don't get it?

It's so simple it's hard for me to think how else to get it through.

Let's try it this way. You want me to think about the processes going on, and you ask if water volume will effect them. My answer is, some processes will be effected, some not.

So, let's choose one of the processes and look at it. We'll take sand vacuuming. Does simply adding more water change this? No.

So - We have the same amount of crud being removed as before, and the same amount of crud being left as before. BUT - The leachate from the crud is now being diluted by double the water volume.

Is there anything not logical? Is there anything I missed? No, right?

Penny dropped?

[lduncan]

So, let's choose one of the processes and look at it. We'll take sand vacuuming. Does simply adding more water change this? No.

So - We have the same amount of crud being removed as before, and the same amount of crud being left as before. BUT - The leachate from the crud is now being diluted by double the water volume.

Is there anything not logical? Is there anything I missed? No, right?

So you're saying that in this case the same amount of waste is being removed,

And the waste which may be leaching back into the tank, is still leaching at the same rate? Right?

And you're saying, even though the waste leach rate is the same, because it is going into more water volume, then the ultimate effect is that the nutrient concentrations in the water is going to be less than what you started with, after adding extra water volume?

Am I understanding what you've said correctly?

[wasp]

Yes, you are just about right.

I will build you a model to help simplify it. The model is "Joes tank".

Joes tank is very simple, so I can eliminate unnessecary debate over things that don't matter.

It is a 100 litre tank, in which Joe keeps a few fish, the tank has been running several years and is stable.

Joe does not have a skimmer, this is so we do not have to haggle over things such as skimmer efficiency. Instead, he exports some DOC's (henceforth called "crud"), by having chemical media in a cannister with forced flow.

He also vacuums the sand each month, which removes 2/3rds of the crud in it each time. He does not believe in water changes though, he lets the crud settle and tips the water back in.

Joe is no scientist but over the years he has found the right amount of chemical media, to absorb all excess crud, and keep the tank as clean as he needs. He changes the media every 2nd month.

The tank does actually contain some crud, in fact, in the water colum are 4 grams of crud. However Joe is happy with that, it is not enough to cause any problems.

He has no liverock, just sand. This is to eliminate any side arguments over liverock.

So Joe has, by trial and error, as most of us do, or at least try to do, achieved a balanced tank. With his sand vacuuming, plus experimenting with how often to change the chemical media, he has got his export to equal his import, there is no slow accumulation of nutrients, it is balanced. Things are not getting any better, but nor are they getting any worse.

In other words he has found the sweet spot to maintain a steady level of 4 grams of crud in his 100 litres of water, or in other words, 1 gram to 25 litres.

To break this down further, Joes feeding of the fish, adds the equivalent of 3 grams of crud per month. As there is no liverock, any crud created, ends up, one way or another, in the sand. However, when he vacuums the sand, this removes 2 grams of crud, and the forced flow cannister of chemical media removes 1 gram of crud each month. A total of 3 grams of crud in each month, 3 grams of crud out each month. Which leaves a total of the steady 4 grams of crud in the water column.

Joe is happy, except for one little annoyance. There is a very slight tinge of algae on the glass, because there is just enough crud to help it grow. Not much, but the algae can just get enough crud to survive on. Joe decides to experiment with extra water volume. he gets another 100 litre tank and connects it to his tank as a refugium, thereby doubling the water volume to 200 litres total. He does not want to change anything else, just double the water volume. He adds no sand, liverock, or anything else, and he puts high flow in the refugium so that no crud can settle in there, it all ends up, one way or another, back in his sand bed, except for what is removed by his chemical media. So when he vacuums his sand, he finds that the amount of crud that comes out is the same as it was before, 2 grams a month, because it is not affected by the extra water volume. The chemical media in the cannister is still removing another one gram of crud each month, the forced flow ensures that it does. So the tank remains balanced, 3 grams of crud a month in, 3 grams of crud a month out, and 4 grams of crud in the water column.

But Joe now notices his algae die. Why? Because the 4 grams of crud in the water column are now spread across 200 litres of water, or 1 gram to 50 litres, not the 1 gram to 25 litres that existed before. So the extra water volume has diluted the crud to the point the algae cannot now extract enough to survive.

Joe now sits back in his couch, knocks the top off his stubby, and takes a swig. Glancing contendedly at his tank, he sighs, and thinks "Thankyou extra water volume. Dilution is the solution to pollution. Big IS More!!" :lol: :lol: :lol: