Plenums and the wasting "option"

[kbmdale]

so basically Now we have come to the conclusion that there are 3 layers in the substrate we should be concerned with. The upper aerobic, the middle anoxic, and the bottom anaerobic....

So If we draw to much we would effectively hender the anoxic because it would be the first area to be introduced to 02....Well there is another variable to be considered.

All three layers are important correct? Is there any reading of info on the precise function and what is broken down in these three layers?

 

[barryhc]

By CaptiveReef:

In this theory the upper layer of substrate is the deeper portion of this bed. The bottom layer is sharing space with the manifold most of the draw point will be around the manifold and just above it. With the 5 second draw these low area's will be only affected, the upper depth of the bed will not be affected so oxygen will not be pulled into the bed.
This way diffusion will be performed naturally in the upper bed, and the waste that has been diffused down to the manifold area can be drawn out.

>>Well, "kinda-sorta", I guess. I can't tell if this is your theory, or my theory. It sounds like a combination of both to me. <bhc>

By CaptiveReef:

You are looking to manually draw the water 1/8 inch at a time through the bed, you would have to draw the water from an uplift tube, like you said a pint at a time every 8 hours.

>>Yes.

By CaptiveReef:

The only problem I see with this is 8hrs enough time for the bacteria to break down the Nitrate into Nitrogen before the next draw.

>>H-m-m-m, If we "draw down" the "entire water column" by .001", and do this 375 times a day, once every 3.8 minutes, then we will move the "entire water column" down by .375" a day. > 3/8" right?

This is going to cause an "oxygen gradiation" to occur within "the entire depth of the substrate". right?

This is going to mean Aerobic conditions at the surface of the substrate, and then "gradually" reducing amounts if oxygen is "we" go deeper into the substrate. right?

The Aerobic area in the substrate will extend farther down into the substrate than it does in "conventional" DSBs or Plenums. I'm not sure how far.

The Anoxic area in the substrate ( which is particularly "thin" in DSBs ) will become stretched ( thicker ), and also extend farther down into the substrate than it does in "conventional" DSBs. Again I'm not sure how much ( thickness ), or how far ( depth ).

The Anaerobic area in the substrate will of course come now, below the Anoxic area, and will extend down to the glass.

This represents an "oxygen gradient" in the substrate

It is my intention to have the plenum "drawing" small volumes of water from this Anaerobic area at the bottom very frequently. That is however frequently is necessary to avoid causing any "undue harm" to the bacteria populations.

If "we" had an oxygen probe at 2" or 3" inches above the plenum, I predict that very, "VERY" little fluctuation in the oxygen "level" would be noted.
< bhc >

By CaptiveReef:

You are going to have to build a prototype and try it, if you have a rise in Nitrates then the process is compromising the DSB.

I installed the prototype 4 mos. ago, and I have not started wasting yet. My Nitrates are < 1ppm currently. When I ( or anyone else ) start "wasting", I think several components in the effluent should be checked.

Oxygen for one, of course!

Phosphate as well, I think.

Nitrates? I think I'll just keep an eye on the tank water, like you say.

I hope this clears things up a "tad bit". I'm just trying to help.

Now about diffusion. Just what does "diffusion" mean anyway? Any thoughts on this, by anyone?

Thanks, Captive reef, and "all"! > barryhc

 

[barryhc]

Kris, You posted while I was typing my reply. It's hilarious sometimes, isn't it?

I agree with you post immediately above! > barryhc

 

[kbmdale]

As far as importance and proccess,

I think the top layers have the greatest job doing the nitrification

the byproduct of that is proccessed further in the second axonic layer

then anything left over is proccessed and stored in the bottom (sink)...

If this is correct, we should be able to move anything we want out of the sink without hendering the tanks biological filtration being doen in the SUBSTRATE....TRUE

If we remove the "sinks" collection of byproducts to fast we will force the 2 areas above to loose effieciece by shrinking the axonic area. If we remove it to slow, we will still allow for a build up which in itself will reduce the anoxic area by having the anaerbic area grow in that way....


MAN we really really have to find the right equation for "waste amount" "Pull duration"....If its wrong we could just be making things worse...


I'm not being Negative, But I am just now seeing the area that will be effected by to little or to much pull, and the bacteria in that area would be the first to suffer. If there were a way to monitor that axonic area of the bed this puppy could be dialed in to perfection....AGREED?????? or am I Just a nutty guy running on to little sleep...:lol:

 

[barryhc]

So, exactly Kris, let's find some of that reading. Randy Holmes Farley, might have some, Eric Borneman R. Shimek maybe, and many others.

The above three might be more toward DSBs, and that's perfectly fine. We needn't endorse "everything" that anybody else says in "it's entirety", either, but reading is good!

This is where I've been trying to go for 3 pages now, I'm very patient.

There is going to be an "oxygen gradation" in the particular system that I am "currently" promoting, and for that system, we have to allow that "bacterial process depths", are not going to coincide exactly with any published information.

In fact, for my case, I don't want them to "conform", I wan't to improve them. Particle size, bed depth, "draw depth and frequency . . . there I go again! :lol:

Let,s find some of this good reading, and maybe define "diffusion" while we're at it.

Thanks again Kris! > barryhc

 

[barryhc]

We're "passing in the night again" Kris. Right again!

E X A C T A M U N D O !!!!!!!!!

> barryhc

 

[barryhc]

Kris, I believe that the Anoxic zone is going to stretch ( get thicker ), and the anaerobic zone will become "somewhat thinner".

"We" need to cause the thickness of the anaerobic zone, to become thinner, but not "gone", thus maintaining, and actually "improving" the thickness of the Anoxic zone. I have been trying to get anyone in the world to understand this for over three mos. now.

It seems like you do! and Thanks again! > barryhc

 

[kbmdale]

Well I understand that I think thats working in a posative way... As long as that axonic area doesn't shrink I don't think the bacteria will be hindered.

So by it growing downward (baby steps) it should make for more effeiciency...RIGHT ON BARRY

 

[barryhc]

We just love that anoxic zone don't we? Let' stretch it a "bit".

Actually when you find some reading on this, "Many" will say that the Anoxic zone only exists for maybe as little as .5mm in a DSB.
I can't say that "it's" true, but you will read it!

You may also read, that the Aerobic zone, exists for only 10mm or so, that would be without the help of "critters" of course, and almost nobody does that, and "cukes", "Nasarrius snails", etc.. will very significantly effect this "depth".

"Depth", I say? What depth ? Diffusion depth? Just what is "diffusion" anyway? Ever hear of "advection"? "Goemans and Gamble" talk abou it, and I under stand it, but I don't ever see it in common use.

Advection depth for us here, is that depth of "pore-water"
flow, that occurs as a function of the flow in the water column.
That would be for us, not from wasting, or bacteria, or from critters, just from water column flow interacting with the particle size in the substrate.

Almost no advection occurs in a "sand bed" ( like typical DSB ) because of the grain size. Some advection occurs in "standard plenums" because of the larger particle size, 2-4mm is common.

So, what is "diffusion"? Thanks > barryhc

 

[kbmdale]

During his MACNA XVI presentation, Julian Sprung discussed his research into the physical effects of water motion on the biological filtration capacity of sediment beds in aquaria. The basic conclusion from that work (covered in more detail in Delbeek, Sprung, In press) is that the location and volume of rock as well as the surface shape of the sand or gravel (e.g., mounds, sloped, or flat) can dramatically affect the efficiency of water flow, oxygen diffusion and nutrient processing in the sandbed. The results we present here likewise argue that there are complex interactions between sandbed depth, particle size and flow that are sometimes counter-intuitive. Obviously, additional research along these lines may prove very fruitful to our ultimate understanding of biological filtration in recirculating aquaria.

http://www.advancedaquarist.com/2005/7/aafeature

I can't answer about diffusion YET...But this article has some really good studies on the sediment size, water flow, and depths....Could be a very useful as far as getting a few numbers and size to rate ratios...

NOw I'm on to diffuse diffusion...

I'll be back later after a doctor visit...

 

[barryhc]

I heard a couple months ago, that Julian was going to present some information that sounded like what I was looking for.

I didn't know that it had become available.

I'm off to read, but I will still be here. Thanks > barryhc

 

[barryhc]

Kris, I did a very quick "skim" on the link that you gave me, and I think I'm already up to date on that.

I don't think that "they" are playing around with "wasting" yet, so "we" have to be careful what we read into any conclusion that "they" come to.

I think it will remain an "important read", let's just be careful about our own conclusions. I like the fact that they are going to include more animals now, I happen to be generally in favor of them, and it is the "whole system", that works or not including "blah- blah-blah" I won't start on that again right now!

Thanks > barryhc

 

[barryhc]

I think another very important "read" for us here is the "BRP" thread I mentioned previously. All kinds of information there regarding Aerobic to Anaerobic and back again, and how this is being used to process Phosphate primarily.

It may not seem to represent what were trying to do here, but, if the downward flow was 5/8" every other day, what would be happening to the bacteria? I'm not promoting anything like this "currently", but it is educational just the same, regarding "draw depth" and "frequency", heh?

I haven't yet found anything else that seems to be "real close" for us. Actually, I think "we" are the ones who are on the leading edge of this! That "we", is "everyone" who is posting in this thread!

Thanks all. > barryhc

ooPS! another "ringy-dingy" 4 seconds ago! :lol:

 

[CaptiveReef]

Diffusion

Diffusion

Well I'll try to tackle the ol diffusion discussion without making a fool out of myself, (I hope).
As we know diffusion occurs in the DSB where the perfect conditions are present to create an anoxic zone.
The actual diffusion is when the bacteria in the anoxic zone use the NO3 to breathe they strip away the oxygen molecule and leave one Nitrogen atom to bubble up as Nitrogen gas. The process of the slow release of Nitrogen bubbles and the introduction of new water into the bed when the Nitrogen is released is the diffusion process.
Hope I got this one?

CaptiveReef

 

[kbmdale]

I think your right on captive. Thats what I am finding in my search for he answer. So would creating a bigger anoxic area for diffusion be benifitial to the tank?

 

[barryhc]

Now that "we've made it to this point, I think that some "layering of the substrate is going to be quite valuable for various reasons.

No, we don't often find it in "the wild" that way. I keep my tank in my "Diver's Den", not . . .

We don't have "wasting plenums" in the wild do we?

Ok, I just couldn't help it, and I'm only referring to the "High Frequency" type of plenum here, that I have been promoting. There may end up being several types of successful "systems" that come out of this investigation, and I certainly hope that is the case!

Just the same, I'm referring in this particular "post" to layering of the substrate that might be conducive to the overall performance and longevity of a "High Frequency Wasting" type of plenum.

Ok, let's start with typical ( or standard ) type of plenum according to "Goemans", and start from there.

Let's try to pull from the center of the tank as much as possible ( details upon request ).

Let's also cram in as many feeder tubes as possible and use lots of rather small holes to "balance flow" across the substrate area.
Calculate these hole requirements to match the flow, don't guess please.

Put in the egg crate and screen just like the "Goemans" model. OOPS!!!! . . . WHOA THERE, HEH?

"Screen", is not very descriptive, and probably works fine in a "Goemans" style plenum, but this "might" deserve some consideration. I have screen on my plenum, and I'm not too worried about it. Mine has about 1.5mm ( or 1/16" ) holes in it.

Now here is where I may "throw" some people off, but I'll take it slow.

Let' start with the larger particles at the bottom, right on top of the screen. How about 3-5mm. That is not "sand", that is gravel. Let's use nicely grade stuff here and rinse it thorughly first .

Why, you ask, I'll get to that later. Let's just keep looking at this "model" for a few more steps here , Ok? Well, alright, I don't want anything to cause blockage around the plenum, you see.

1/2 " deep of this gravel should probably suffice from a "flow" standpoint. "But what about the anaerobic bacteria", you say, yeah, they'll be there, what about them?

Ok, how about, say, 1"depth of 2-4mm gravel above that? What's that for, you might ask? Well, . . . "Goemans" uses up to 4" depth of this stuff, so are you asking if it is too much, or too little?

The "hope" here is, that there is a lot of Anoxic activity in this "level" of the substrate. How thick is this Anoxic zone anyway, that everyone seems to know so much about? Remember the .5mm thickness of "Anoxic zone" mentioned previously in regard to DSB's?

All right, so here is where get to start "playing with it".

Now the 2-4 mm layer of gravel, is going to block "particle migration" down to about .3mm, that is three tenths of one mm. Don't think so, heh? Try me! Sorry, can't help it on occasion.

If you want to go with particles smaller than that, you may want to add, yet another layer of .7 to 1.7mm particles, say another 1/2" to 1", whatever.

Let's see now, were at 2" to 2 1/2" deep now right? ( from the "bottom up" )

Well, what do you want to do with it now? That is up to you of course, but for me . . .

Well I,m not going to be having "plugging issues" in the plenum now, because, I'm blocking "particle migration" with the afore-mentioned "larger gravel".

This seems a little bit counterintuitive, doesn't it? That is how I see it working.

Ok, for me, it is now a matter of what "critters", that I ( "we" )want to keep. H-m-m-m . . .

Let's put in a second screen here, to keep the "critters" from messing with our carefully controlled lower layers, heh? I'm thinking 6mm plastic mesh. I'm only trying to stop critters here, nothing else!

I like crabs, and snails, and pods, and cukes maybe, . . . micro stars maybe? Geeze, this is the part that is interesting here, because these animals could have some effect on the the "Oxygen Gradient" in the upper level of the substrate. right?

I think I might try some .7-1.7mm here, but I'm not so sure about how deep. The Gobies might like 3" of this, but that may not suit the "oxygen gradient" I'm looking for.

Oh well, more investigating to do!

What's next? > barryhc

 

[barryhc]

CaptiveReef, I like your definition of diffusion. Thanks, I'll use that definition now. It sounds like a good one.

Thanks again! > barryhc

 

[CaptiveReef]

Diffusion

Diffusion

I think your right on captive. Thats what I am finding in my search for he answer. So would creating a bigger anoxic area for diffusion be benifitial to the tank?

Yes to make the area bigger it would have to be not deeper, but larger over an area, (square footage) A tank that is greater in depth(front to back) would have a better anoxic area than a tall tank.



CaptiveReef

 

[CaptiveReef]

Plenum/wasting

Plenum/wasting

Now that "we've made it to this point, I think that some "layering of the substrate is going to be quite valuable for various reasons.

No, we don't often find it in "the wild" that way. I keep my tank in my "Diver's Den", not . . .

We don't have "wasting plenums" in the wild do we?

Ok, I just couldn't help it, and I'm only referring to the "High Frequency" type of plenum here, that I have been promoting. There may end up being several types of successful "systems" that come out of this investigation, and I certainly hope that is the case!

Just the same, I'm referring in this particular "post" to layering of the substrate that might be conducive to the overall performance and longevity of a "High Frequency Wasting" type of plenum.

Ok, let's start with typical ( or standard ) type of plenum according to "Goemans", and start from there.

Let's try to pull from the center of the tank as much as possible ( details upon request ).

Let's also cram in as many feeder tubes as possible and use lots of rather small holes to "balance flow" across the substrate area.
Calculate these hole requirements to match the flow, don't guess please.

Put in the egg crate and screen just like the "Goemans" model. OOPS!!!! . . . WHOA THERE, HEH?

"Screen", is not very descriptive, and probably works fine in a "Goemans" style plenum, but this "might" deserve some consideration. I have screen on my plenum, and I'm not too worried about it. Mine has about 1.5mm ( or 1/16" ) holes in it.

Now here is where I may "throw" some people off, but I'll take it slow.

Let' start with the larger particles at the bottom, right on top of the screen. How about 3-5mm. That is not "sand", that is gravel. Let's use nicely grade stuff here and rinse it thorughly first .

Why, you ask, I'll get to that later. Let's just keep looking at this "model" for a few more steps here , Ok? Well, alright, I don't want anything to cause blockage around the plenum, you see.

1/2 " deep of this gravel should probably suffice from a "flow" standpoint. "But what about the anaerobic bacteria", you say, yeah, they'll be there, what about them?

Ok, how about, say, 1"depth of 2-4mm gravel above that? What's that for, you might ask? Well, . . . "Goemans" uses up to 4" depth of this stuff, so are you asking if it is too much, or too little?

The "hope" here is, that there is a lot of Anoxic activity in this "level" of the substrate. How thick is this Anoxic zone anyway, that everyone seems to know so much about? Remember the .5mm thickness of "Anoxic zone" mentioned previously in regard to DSB's?

All right, so here is where get to start "playing with it".

Now the 2-4 mm layer of gravel, is going to block "particle migration" down to about .3mm, that is three tenths of one mm. Don't think so, heh? Try me! Sorry, can't help it on occasion.

If you want to go with particles smaller than that, you may want to add, yet another layer of .7 to 1.7mm particles, say another 1/2" to 1", whatever.

Let's see now, were at 2" to 2 1/2" deep now right? ( from the "bottom up" )

Well, what do you want to do with it now? That is up to you of course, but for me . . .

Well I,m not going to be having "plugging issues" in the plenum now, because, I'm blocking "particle migration" with the afore-mentioned "larger gravel".

This seems a little bit counterintuitive, doesn't it? That is how I see it working.

Ok, for me, it is now a matter of what "critters", that I ( "we" )want to keep. H-m-m-m . . .

Let's put in a second screen here, to keep the "critters" from messing with our carefully controlled lower layers, heh? I'm thinking 6mm plastic mesh. I'm only trying to stop critters here, nothing else!

I like crabs, and snails, and pods, and cukes maybe, . . . micro stars maybe? Geeze, this is the part that is interesting here, because these animals could have some effect on the the "Oxygen Gradient" in the upper level of the substrate. right?

I think I might try some .7-1.7mm here, but I'm not so sure about how deep. The Gobies might like 3" of this, but that may not suit the "oxygen gradient" I'm looking for.

Oh well, more investigating to do!

What's next? > barryhc

I like the progress!!!!! barryhc if I may suggest doing a 2inch bed with the manifold,the screen layer then 4 inches of sand on top.
Just a suggestion, those depths work pretty good for me as a regular DSB.

CaptiveReef

 

[barryhc]

By CaptiveReef:

I like the progress!!!!! barryhc if I may suggest doing a 2inch bed with the manifold,the screen layer then 4 inches of sand on top.

>>Are you still suggesting to "draw" from somewhere in the "mid-level" of the substrate depth? Is that putting the "manifold" above a 2" thick "lower bed", and under a 4" thick "upper bed"?<bhc>

By CaptiveReef:

Just a suggestion, those depths work pretty good for me as a regular DSB.

>> I imagine those depths would work pretty well, for a "regular DSB".

Did you catch the part about "particle migration" and not "plugging up" the plenum?

Just checking. > barryhc