razoreqx
Active Member
(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.
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.
thanks for posting, that's good stuff.
