Refugiums

[wasp]

So, how does adding water volume, make the amount of rock in a system increase?

It doesn't. I think you're being silly. :lol:

Better for water quality, or better for livestock health? There is a difference.

Both

The confines aren't narrow at all, .

Only considering the skimmer, nothing else, is narrow.

and it seems I'm not the only one with this opinion. The guy in that link obviously thinks so too..

The guy in the article claims from the outset that he is discussing skimmer export only.

[lduncan]

Wasp, what you're trying to do is bring in "other factors" which are totally unrelated to increasing water volume. Then attribute any effects from these unrelated changes to the added water volume, when in reality it has nothing to do with water volume.

Then in your mind you see the fact that I haven't considered these completely unrelated factors, as the model being narrow. When in reality it's the model modelling exactly what it's suppose to.

Layton

[wasp]

No you are confused.

[wasp]

Perhaps you would understand better if you actually read what Feelers said and consider it.

Moving ahead with your pre planned series of points, regardless of what anyone says, will not carry the day for you.

[wasp]

Also, still waiting for an answer to this :-

For nitrate and phosphate?

You sure about that?

How do you know?

[puttputt]

well, I'm off to get another fish tonight, no worries with all that extra water volume that my refugium gives me :lol:

Misnomas hawkfish actually.

[wasp]

I've heard your acros are climbing out the top!

That's where I think that more volume benefits by a more steady trace element supply.

[lduncan]

That's where I think that more volume benefits by a more steady trace element supply.

Exactly.

[puttputt]

So if it doesn't make any difference in water quality, is better at buffering Ca, Mg, etc, and provides excellent food for your tank, wheres the argument???

Aren't we going around in circles here??

[puttputt]

I've heard your acros are climbing out the top!

should have kept quiet, people lining up to break pieces off now

[lduncan]

Well if you remember, someone claimed that extra volume reduces nutrients by dilution? Which is wrong, it doesn't.

Comes back to doing something for valid reasons.

If you add more water volume in an attempt to lower nutrients, you're going to be disappointed.

If you add more water volume in an attempt to reduce fluctuations in resources like Ca, Mg, HCO3 etc, then you will be happy.

Making broad sweeping statements like "big is good" isn't always useful.

In this case big isn't necessarily good in terms of nutrient concentrations, it's no change.

[wasp]

But you have failed to show that, for example, with nitrate.

[Jeroen]

Has anybody had a play with the simulator I posted? I was waiting for some comments.

Again this only looks at skimming but if we increase the tank size in the model the water quality deteriates (or better said it takes much longer to remove all DOC). It takes more effort to get the all the DOC to the skimmer.

Still take into acount what this mean in practise. The model show how long it takes for a skimmer to remove DOC. Like when you add fish food. Only the model assumes that all DOC is evenly distributed at the start what clearly is not the case. Still without the model I would not have thought about this point.

[wasp]

Yes the simulator is correct.

Even Layton has not yet considered it, he could have got some mileage out of it :lol:

It is another example of wher Laytons narrow model falls down also, brings up points he did not build into his model.

[lduncan]

The model is virtually the same as the one I came up with, with the inclusion of a few variable which I had accumulated into the "efficiency factor", and a model of diffusion, which only changes time scales, not the trends and end results.

Really the only difference is that the transients are shown a bit better.

But the trends and end results are the only things you can take from these models.

[lduncan]

Yes the simulator is correct.

Even Layton has not yet considered it, he could have got some mileage out of it :lol:

It is another example of wher Laytons narrow model falls down also, brings up points he did not build into his model.

I think you're confused.

[lduncan]

But you have failed to show that, for example, with nitrate.

Maybe it was just over your head?

[wasp]

Maybe you failed to show it

[lduncan]

Maybe you failed to understand it?

[wasp]

I think you're confused.

Hardly, you have already admitted there are more variables than your model, here.

The model is virtually the same as the one I came up with, with the inclusion of a few variable which I had accumulated into the "efficiency factor", and a model of diffusion, which only changes time scales, not the trends and end results.

I've been trying to get this fact across to you for a while. Don't take it from me though, huh.

So you are getting there slowly, but even now you are still not considering all the variables.

What was it you said went over my head?

[wasp]

Maybe you failed to understand it?

Please show me where.

I'll be intersted in your discourse on nitrate

[lduncan]

Hardly, you have already admitted there are more variables than your model, here.

Umm, all those variables are actually considered in my model. Just because they don't appear as independent variables, doesn't mean they are not factored into it.

I've been trying to get this fact across to you for a while. Don't take it from me though, huh.

So you are getting there slowly, but even now you are still not considering all the variables.

What was it you said went over my head?

The point i've been trying to make, which has gone over your head is that just because these variables exist, doesn't mean that you have to explicitly separate them in the model. It's quite acceptable to combine the variables into a scaling factor (whether linear not not), and focus on the variables of real interest, the ones that define the trends and endpoints. That model in that link shows exactly the same trends and endpoints as the one I proposed earlier.

Just take a step back, then you might be able to see the forest from the trees. You're getting bogged down in detail, trying to include every possible variable, and making it controllable controllable. It's totally unnecessary. I'm not saying ignore them, but all you need to do is consider them, and there range of effect, and then bundle all the uninteresting ones into scaling factors, it makes it a lot easier to see what's really going on in steady state, ignoring the specifics of the transients.

The whole idea of modelling is to make it as simple as possible to get the required information out of it. The more detailed the model the more specific information you can get out of it.

For the purposes here, the model I came up with is good enough, and is totally consistent with the model on the site linked.

Layton

[wasp]

The point i've been trying to make, which has gone over your head is that just because these variables exist, doesn't mean that you have to explicitly separate them in the model. Layton

In order to get a correct end result, the variables may not have to be seperated. But, you do have to actually have them in the model. Wether seperated or not may not be so important, but if they are missing altogether will likely have an impact. That's the bit that keeps going over your head.

For example, you do not include in your model any allowance for the fact that nitrate is primarily exported from the tank by means other than the skimmer. So, if you narrow it down so that in your model, ALL export is done by the skimmer, nothing else, your model does not reflect a real tank.

Can you see that now?

For the purposes here, the model I came up with is good enough, and is totally consistent with the model on the site linked.Layton

I'll agree with that, if by "the purposes here", you mean nothing other than the relationship between x amount of skimming, x amount of dirt, and x amount of volume. Your model will show that, and so will the one in the link, as that was all it was designed for.

However, you have stated that the reason for all this argument was to try to prove Cracker wrong when he made a comment about increased volume.

You need to realise that Cracker was talking about a real tank, not a model that only allows one form of export, a skimmer.

So as long as you continue to doggedly stick to your skimmer export only model, you will likely convince yourself of your argument, but you will not convince me, or Cracker, or anyone else, who realises that in an actual tank there are other forms of export, for example processing of nitrate by liverock, vacuuming of sand, etc. These other processes throw your skimmer only model, neat and tidy as it is, right out of whack.

So while, as you keep saying, I cannot see the forest for the trees, at least I know what the tree is. :lol:

[lduncan]

your not listening, i've said that those variables have been considered in the creation of the model, and do exist in one form or another, just not in an explicitly controllable form. That's the part which you keep missing.

so how does adding water change the processing of nitrate in live rock? how does adding water change the vacuuming of sand?

[wasp]

your not listening, i've said that those variables have been considered in the creation of the model, and do exist in one form or another

So where is vacuuming of sand in your model? It is not there. Is it.

You are the one who is confused.