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Razoreqx
04-28-2004, 02:12 PM
(Controlled Plenum Wasting).

I know the DSB followers will say come back in 5 years when you have proven it works. My response is it does not take years to prove positive results and the system can at any time be made into a Jauberet of DSB by simply not using it, so there is no risk in using it. I also believe for newly established systems, that are set up with CPW, reef keepers will have a much greater chance of long term success.

CPW is based on and assumes the DSB and the Jauberet systems do not work well as biological filters. That is not to say oxic and anoxic biological filtration is not taking place in them, but that it is just terribly inefficient and uncontrolled biological filtration. It assumes at best you can walk a tight rope using them, and make them appear to be functioning, only to have a disaster a few months or years into their operation. If these systems are kept biologically very lightly loaded they may appear to be functioning, when they in fact may be doing more harm than good by slowly or abruptly allowing uncontrolled anoxic septic fluid to flow back into the system or deal with a potential death bomb if you stir up the bed.

If the above is true, why should I not simply use a BB (bare bottom)? The more biological useable and functioning biological surface area you have in a tank the better. It helps to keep the tank stable from the increased biological loading when sudden death or overfeeding occur. It is the same reason the use of live rock has been so successful in making reef tanks possible.

CPW (Controlled Plenum Wasting)

1. It assumes the fluids in the bottom of a DSB are anoxic and are not fully stabilized.

2. It assumes anoxic waste can buildup at a faster rate than the available bed active biological surface can fully stabilize it.

3. It is designed to remove unprocessed or reconstituted nitrates, nitrites, ammonia, phospahtes and other organic waste that accumulates in the bottom of the bed.

4.It assumes DSB and Jauberet designs are not 100% effective in biological stabilization, and infact do cause a major build up of anoxic Hydrogen Sulfide in the bed that does and can leak back into the tank.

5. It is simply a method to compensate for this inefficiency.

6. It improves the DSB biological efficiency by moving fresh food into the zones.

First I will address a major DSB and Jauberet process fallacy often stated.

1.) Anaerobic processing is completely stopped if anoxic fluid( partially oxygenated) moves into a DSB zone and it takes weeks to recover. All of the waste I remove does not show that to be factual.

You do not need or want large low or no flux dead zones in a DSB. You want a positive low transport rate of fresh septic material into and out of these zones. Depending completely on critters in a bed to do this is foolish. Most critters do not like to go into the large anoxic sulfide laden zones that quickly build up.

What is CPW (Controlled Plenum Wasting)? I will given a concise description of how I built my system and how it works. It is not very complex or should it be highly controversial, except for the fact that it may be viewed a heresy by advocates of DSB's. It is really based on common sense. It simply keeps a more positive flow into the bed and not back out into the tank water column.

In my system I have installed a plenum piping system, at the bottom of the bed, with relatively low very small number of orifices. I do use a coarse uniform agronite crushed coral as a DSB media (Carib Sea Special Grade Sand). This is all to assure of a more even flow distribution across the bed. A conventional commercial bottom filter, with is large open area, can and will rapidly short circuit the flow.

On a daily basis I drain the plenum of a couple of pints of anoxic waste that accumulated.

That is all there is to the system.........

I have the drain valve controlled with an X10 switch and my computer. It drains out a small amount every 8 hours.

Set up- Reef Tank: 45g half barrel, 30Hx15Dx30W, 5" DSB with a plenum bottom filter from which I drain 1 couple of pints of waste daily, Carib Sea Special Grade Sand 40 lb, 40Lbs Fuji branch LR, 15 G BB Fuge, Kalk Reactor, Skimmer, Ozone feed.

Why do I say this approach works better than other approaches that try to neutralize all the waste within the bed. It is based on very obvious measured results over two months.

1. What is drained out is always anoxic and has a rotten egg smell. Not something you want to remain in the tank. The fluid drained is anoxic, pH of the wasted fluid is always .5 lower than the water column, three to four times high ALK readings in the wasted fluid; all of which are an indication of continuous biological sulfide processing taking place deep in the bed.

2. When I have purposely allowed even a small amount to this anoxic sulfide laden fluid to re-enter the tank, the tank ORP read out drops like a rock and takes nearly a half day to recover. Even with the addition of ozone into the skimmer.

3. I have stopped making weekly 25% water changes.

4. My ORP readings have never been higher, they are approaching 400 mv. . Infact they remain above the ORP 350 mv set point for ozone feed and are continuing to increase. Little to no ozone is now even being added to the skimmer.

5. My water quality continues to improve, and all of the coral are responding positively to the water quality.

Is the above proof positive that this approach has merit? It does for me. Sure I will continue to monitor and tweek the wasting rate to see if I can improve upon the result. I am sure other will improve upon this approach and I will continue to monitor and post the good and bad.

I have experienced no negatives. My tank is very stabile with very low ORP swings and much more rapid recovery. I no longer do weekly water changes, which was a pain in the butt. The total amount of water removed is a small fraction of that need during normal water changes.

Some of the other potential but unproven positives.

http://www.ozestuaries.org/indicato..._reduction.html

Organic matter decomposition can be a consequence of sulfate reduction in the sediments of coastal waterways (and other aquatic systems) [1]. The process is performed by anerobic sulfate-reducing bacteria. The bacteria require: metabolisable organic matter ; an anoxic environment (or microenvironment); and dissolved sulfate. Hydrogen sulfide gas (H 2S) and alkalinity are generated in the process (see simplified reaction 1).

Consequences of Sulfate Reduction

H2S smells like rotten eggs, and can detract from the aesthetic amenity of coastal waterways when it is released to the atmosphere [2,5].

H2S is toxic to a wide range of aquatic organisms [3];

H2S can inhibit nitrification [4]. When nitrification is inhibited, coupled
nitrification-denitrification is also inhibited.

Ammonium (NH 4+) is released from organic matter during degradation by
sulfate reduction (Equation 3) [6]. Ammonium is a bioavailable and is
readily taken up by plants.

(Eq. 3) 106(CH 2O)16(NH 3)(H 3PO 4) + 53SO 42- “106 CO 2+ 16 NH 3+ H 3PO 4+
106 H 2O + 53 S 2- Iron sulfides ( e.g . pyrite), formed during sulfate
reduction, are an active component of acid sulfate soils (***),
and problems with acid production and drainage can arise if the pyrite
is oxidised .

Iron sulfides cannot bind phosphate . Therefore, when iron oxyhydroxides are converted to iron sulfides during sulfate reduction, phosphate can be released to the water column [9].
__________________________________________________ ____________

The above leaves little doubt in my mind as to why a conventional DSB is a crap shoot and a ticking bomb. I will continue to run my experiment with removing this sulfide rich waste soup to see if a DSB can be made to work. Without a method of removing all of this bad soup from the bottom of any DSB I don't believe they can* work. *(can is relative. I mean eventually fail)

I personally believe your odds at the crap table in Vegas are better than you odds of having a reef tank using a DSB more than a few years before it flips or leaks back into the tank killing everything. If you had a strictly SPS tank with few fish you may beable to stretch the tank life out a few more years.

Phosphate non-binding can be a problem with a DSB, but the biggest advantage of a BB, and only using live rock, is that you have very little sulfate reduction zone to cause an upset. The negative is you have greatly reduced biological processing surface.

With a BB don't have a big hot cauldron of anoxic sufide soup that a DSB can produce. It is loaded with ammonia, nitrates, is nitrification inhibiting , toxic H2S laden, and an oxygen depleting soup building up in a DSB waiting to boil over and snuff out life.

Charles Poole
04-28-2004, 10:18 PM
Hmmmmmmmmmmm. I wonder what kind of interesting debates this article will stir up... :)

Excellent article. My thinking gears are definitely going into overdrive.

Paidbychrist0825
04-29-2004, 11:04 AM
glad i read this before tank was up. i might try this.. i have a question though... now when did you start pulling water(waste, w/e) out through you little bottom pump thingy? like right off the bat, or like a couple monmths in?

Razoreqx
04-30-2004, 10:19 AM
I started about four weeks after the refugium was setup. If your using the display tank I would say start right after your cycle is over and your doing your weekly water changes.. I do these small pulloffs rather than my 20% water changes i use to do.

Charles Poole
05-02-2004, 10:42 AM
razor,

Get in touch with my via PM.

MikeS
05-02-2004, 10:53 AM
Interesting....how long have you used this method in your tank?

Have you had DSB's in the past? Mine is 3 1/2 years old and no problems so far....

Mike

Charles Poole
05-02-2004, 12:22 PM
Check the articles section for an editted and formatted version of this article.

Here is a link to it:

Controlled Plenum Wasting (http://www.coralforum.com/reference36.html)

icereefer
05-02-2004, 01:10 PM
There again,I love this hobby :-D
I know hobbyists that have used plenums for years and still do with great success, and I know some that had nothing but problems and went DSB. same with DSB's.
myself I'll go with mother nature, because I now the Ocean has no plenum under it.
like in my DSB and in the Ocean's everything in there has it's purpose for existing,and understanding what that purpose is,is the key to successful reefing, IMO.
most of my problems I've had in my DSB is not understanding the purpose of my detritivores,ect and the more I learn about my life cycle in my tank, the more it thrives. me and like others are still researching and will be for years on the evolution of life,and until that day comes. does any one really know what is the right way is.

Not to diss your post because it's very,very well written and makes a lot of sense, but then again DSB do too.
peace awesome insight.

Charles Poole
05-02-2004, 02:53 PM
Yea, I agree that without a true understanding of the exact processes nature uses to keep the reefs the way they are, we are just "guessing" with hopes of success.

I still run an undergravel filter in my 20 gallon nano-reef. I see posts all the time about them being bad or not recommended. The only thing I can come up with for these claims, are that a suffiecient amount of water flow was not employed. I run a Hagen 802 powerhead wide open in my 20 gallon which is attached to the pickup tube of the UGF. If the filter gets clogged ( which happens approx. once every 2 weeks or so, snails clog the pickup ), then the tank immediately starts to show signs of unhappiness. I unplug the pump, clean it out, and viola. The tank returns to it's normal state.

I think that the CPW system has some potentially benefits over the other two systems, in that it does not require the countless populations of microorganisms, that the DSB and Plenum systems require in order to function. These organisms are mostly sand bed dwelling creatures, so LR is not a likely source most of the deeper dwelling sand organsims. And obtaining a "seed" kit, may not be all that practical for most people.

I am going to setup a 30 gallon tank with this setup, and see what happens.

razor,

Could I use and UGF plate and some nylon screen to create to plenum area for this system?

MikeS
05-02-2004, 05:42 PM
Razor-
I noticed you said you use a course grade sand on top of the plenum...what is the grain size? Do you do this to allow a faster rate of water diffusion to the lower part of the DSB?

Chuck...UGF in your 20 gal? Interesting...do you use powerheads to push water through it? How long have you used it in your 20 gal.? Do you experience any nitrate problems with it? I'm admittedly one of the ones who recommends against UGF's, but if you have found a way to have success with them, I'd be curious to know what the trick is! :D

Mike

Charles Poole
05-07-2004, 09:20 AM
I set the tank up with an UGF. I do run a strong Hagen Powerhead 802 on this UGF, with approx. 2 1/2 inches of dolomite covering it. The bed is kept clean by the multitude of Bristle worms that live in it.

I do have to pay close attention to the pick-up on the Powerhead though. If the flow is reduced, then things don't look right. Eaasily corrected by unclogging the powerhead.

I perform WC about 1 every 2 months or so. This is by far my most stabile tank. It houses a Heteractis ?malu? anemone, Skunk Clown, Coral Beauty Angel, T. dersa clam and a large Green Tree coral.

I also run an air-driven skimmer on this tank, but it is set to add more oxygen, and not to remove wastes. I use caulerpa macro algae to do the majority of excess waste removing. :)

PS. The dolomite was used to see if I could acheive any benefits of extra Magnesium when it dissolves. So far, things appear to be working well, but I have not been able to tell if I am receiving any extra magnesium from the dolomite. But the grain size is great for the bristle worms to thrive in...

Razoreqx
05-08-2004, 08:05 AM
Razor-
Q: I noticed you said you use a course grade sand on top of the plenum...what is the grain size? Do you do this to allow a faster rate of water diffusion to the lower part of the DSB?


Reply: I used a large grain sand.. Its not sugar sized. I dont know how else to describe it. I'll get some pictures. And yes it allows for a more equal suction of material from the bottom of the tank.


razor,
Q: Could I use and UGF plate and some nylon screen to create to plenum area for this system?

Reply: Wow thats a great idea! Let me know how that turns out. Yes it seems to me that it would work, and actually work better than the corse sand.

Ghosty
05-10-2004, 11:32 PM
...With a BB don't have a big hot cauldron of anoxic sufide soup that a DSB can produce. It is loaded with ammonia, nitrates, is nitrification inhibiting , toxic H2S laden, and an oxygen depleting soup building up in a DSB waiting to boil over and snuff out life.
Are you also pulling Phosphates out when you do the draining?

MikeS
05-10-2004, 11:48 PM
I'm also doing more research on this....BUT, IMO the toxicity of the DSB reflected here is a bit exaggerated....

Mike

Ghosty
05-23-2004, 06:24 AM
I've been reading the other thread (w/ you & Mojoreef) on DSB's, sounds like one of the debates is on the grain-size posed here. What about in a hybrid setup like I'm considering here?:

60-gallon hex, with CPW UG plate, 4-6" DSB as setup by author here, and also have 75-lb. of live rock over that will help make up for the lesser dentrifying surface-area (larger grain size than sugar-sand).

Excuse the "semi-noob" question, but I've been out of the game for several years, so DSB will be new for me...

Ghosty
05-23-2004, 06:29 AM
Check the articles section for an editted and formatted version of this article.

Here is a link to it:

Controlled Plenum Wasting (http://www.coralforum.com/reference36.html)
That article doesn't seem to be linking for me (error). If possible can you either repost or e-mail me the article? ---> Ghosty427@comcast.net
Thanks. Another question: What kind of plenum are 'you' using? I'm also considering my UG-plate with screening...

MikeS
05-23-2004, 04:20 PM
These are defiantely not "noob" questions, Ghosty! :D

I think the CPW idea has potential. The main problem I have with it is I think in order to get this system to function properly in a mechanical sense, the grain size required to be used in the substrate will be too large to provide adequate denitrafication. A stratified DSB may be a partial solution, but I think with the increased rate of diffusion through the sand bed caused by pull from the plenum will create migration problems, and it will eventually clog.

Mike

Ghosty
05-23-2004, 06:03 PM
Hopefully Razorgx will post a nice 'one-month' update soon here. I'm curious what his bioload is. I'm probably going to do a very similar setup to his, except in my 60-hex which is very deep, so ideal for a DSB w/ CWP. Since my bottom is tempered (no drilling allowed), I am trying a custom design:

My CWP will be a 60-hex UG-plate with 1" plastic piping at various support points, the whole thing wrapped in nylon screening (or whatever is ideal). Keep the normal back pipe that runs as high as the aquarium, but instead of a powerhead at the top, I'm running a bunch of soft aquarium airline tubes (4-6) down that big tube. They will spread out under the UG plate (but inside the screened area, and the ends of each tube will be under various points , maybe even poke some holes in these lines at various points. The other ends of these tubes will run out the top of the UG tube, and out the top/back of the tank, down to combine into one larger plastic tube (using silicone), with a drain valve, then more tube into a waste-bucket. (I'll think about the fancy homePC-controlled valve later on, heheh)

Computer-controlled waste-draining: Since this is all (easily) set by computer software, why not drain even smaller amounts at more frequent intervals, as if mimicking a steady but "ultra-slow" current down thrown the bed?...

MikeS
05-23-2004, 06:06 PM
Ghosty....what kind of substrate do you plan on using on top of the plenum?

Mike

Ghosty
05-23-2004, 06:09 PM
Ghosty....what kind of substrate do you plan on using on top of the plenum?

Mike
I'll be using a stratified DSB, with 2-3" of the regular coarse sand (what Razorgx uses or similar) over the plenum, another hex-shaped screen separator, then 2" of fine LS (seeded with 20-lbs. of a friend's LS). That's the bed.

Over this is placed 75-lbs of established LR. I'm hoping this amount of LR, and the slow bottom-draining is enough to compensate for the lesser denitrifying area of the coarse-sand portion of the bed...

My filtration (so far) will be a large Skimmer, lighting a single MH pendant (175 or 250-watt, not sure). A medium-size Refugium will be added after a month, once the tank is settled in and I can see what's going on.

MikeS
05-23-2004, 08:20 PM
Good plan so far....I think that some sort of stratified bed could be the answer....

Even with a screen, however, I'm still concerned about the fines migrating down within the fine sand protion, potentially packing in too tight and "clogging" it up, esp. with H2O pull under it.

Mike

Ghosty
05-24-2004, 02:52 AM
I was thinking about that also, hence the (smaller) 2" (live) fine-sand layer. Hopefully all the worms, etc. will keep it relatively mixed. Plus I'm still going back and forth between this CWP vs. a near-bare-bottom with only LR and a refugium, but I'm afraid the latter won't be able to handle the bioload of more than few fish. I'd like to be able to keep at least 8 small-medium fish.

MikeS
05-24-2004, 08:56 AM
An NBB with a refugium IMO should be able to handle a similar bioload, with adequate skimming and religious maintenance practices on your behalf.

Like I said, I think some sort of stratified substrate may be the key to making CPW work properly. If you choose this method, be sure to keep us all up to date on your progress...including any problems this system presents, either mechanical or biological...

Best of luck, I hope it works well :D

Mike

Ghosty
05-24-2004, 06:49 PM
...If you choose this method, be sure to keep us all up to date on your progress...including any problems this system presents, either mechanical or biological...

Best of luck, I hope it works well :D

Mike
Thanks! I'm painting my stand right now, this weekend might be the big setup if I get the tank all cleaned, and the various plenum parts together. I'll update ya guys later.

Condiman
05-30-2004, 03:07 PM
Reading all these posts really got my wheels turnin. How long has this CPW been around?

dx7fd2
06-17-2004, 09:36 AM
Ghosty:

Q: I'm running a bunch of soft aquarium airline tubes (4-6) down that big tube. They will spread out under the UG plate (but inside the screened area, and the ends of each tube will be under various points , maybe even poke some holes in these lines at various points.

Are you going to be using gravity to drain the liquid out or some type of pump to suck out the substance under the plenum?

Hello, by the way, I'm a newbie in these here parts!! :wink: