Duplex sump concept

IMO, chaeto is for removing nitrates and xenia is for particulate matter. These are used to export two completely different animals: nitrate-phosphate versus food-waste particles in the water column. I would say that some LR rubble and about 1" LS will process just as much particulate matter after it becomes established with pods and worms. The xenia is a pain b/c it's just another draw for electricity since it requires moderate light. Chaeto and all the invasive species of algae I have require only light from 23W/16W CFL flood lights and receive supplemental lighting from a window. I prefer refugiums for particulate removal when I'm not running a filter sock. Another idea I've thought about using is sun corals as a first stage of a sump to sump as much particles from the water, but have not grown out my colony nearly large enough for this task.

BTW...were you on or currently on PU SAE Formula? Just wondered as I was on Baja for about 5 years.
Awesome thanks, so putting chaeto in the sump, then having an isolated "island" of xenia in the main would work wonderfully then.

And I'm on PU Solar Racing, but I have a lot of friends in Formula, not so much in Baja though
 
I would be lying if I said I knew the best way to filter a reef aquarium. The delicate balance between nutrient import and export, and bacterial assimilation (nitrification) and dissimilation (denitrification) is the true challenge of the hobby.

We know that our captive reefs have a surplus of trace elements (heavy metals). These can be removed chemically or mechanically, as they are usually attached to detritus (POC), so in many ways a mechanical filter is a chemical filter. A significant amount of bacteria is attached to detritus, both in the substrate and free-floating in the water column. Protein skimmers and filter socks remove POC, bacteria, calcium, zooplankton, and heavy metals. Some of these elements are "good" and some are "bad". The good stuff is easily replaced with nutrient import (feeding).

My conclusion is... feed well, filter "weller". As long as you maintain adequate marine snow in the water, the corals and fish will thrive and with a collection of seemingly superfluous filtering devices, you can remove residual Po4 (phosphate) & No3 (nitrate).

There is no shortage of filtration options, some more valuable than others. You must weigh the initial cost, operational cost, maintenance, convenience and residual to measure their merit. I find filter socks to be cheap and easy with little residual if you have the time to clean them at least twice a week. The bacteria removed by skimming are only the free-floating "castaways" from the exponentially larger colony of bacteria in the substrate so lower bacteria rates in the water column doesn't bother me. Sponges primarily consume bacteria so a benthic/cryptic zone would lower bacterial counts, and a skimmer limits the growth of sponges.

Bacteria is easily fostered with the addition of a carbon source such as vodka, vinegar, glucose or biodegradable polymers. In my opinion, the carbon source should be added directly to an anaerobic bacterial bed, rather than poured randomly into the water column. The danger with low nutrient systems is you deprive corals of inorganic (dissolved) nutrients. You must compensate for low inorganic nutrients by increasing organic nutrients. A partially automated system that slowly adds zooplankton and phytoplankton will make up for our mini waste water purification plants.

I have had good success with non-hatching decapsulated brine shrimp eggs, finely ground plankton, and frozen cyclops. Some people swear by oyster eggs, but I can't justify the cost.
 
From some reading that I did yesterday, activated carbon has a significantly greater afinity for organic compounds than it does for metals/trace elements, but it will remove trace elements. What I'm not sure of is whether or not activated carbon (1) would absorb a trace element compound and hold on to it or (2) if it will release the compound when an organic compound with a higher afinity comes around and bind that organic compound instead. If the second situation is the case, than the affects on the removal of trace elements would be minimal once the carbon is sufficiently saturated with organics.

Trace elements are attached/bound to larger organics attracted by activated carbon. Carbon should be changed once it has exhausted its absorption capacity as it will release its catch.

I have access to an optical emmision spectrometer at work and I might be able to put together an experiment to figure this out. However, don't hold your breath. I'm usually kind of slow to getting around to these sorts of things...

Well that sounds a hell of a lot better than work :)
 
I would be lying if I said I knew the best way to filter a reef aquarium. The delicate balance between nutrient import and export, and bacterial assimilation (nitrification) and dissimilation (denitrification) is the true challenge of the hobby.

We know that our captive reefs have a surplus of trace elements (heavy metals). These can be removed chemically or mechanically, as they are usually attached to detritus (POC), so in many ways a mechanical filter is a chemical filter. A significant amount of bacteria is attached to detritus, both in the substrate and free-floating in the water column. Protein skimmers and filter socks remove POC, bacteria, calcium, zooplankton, and heavy metals. Some of these elements are "good" and some are "bad". The good stuff is easily replaced with nutrient import (feeding).

My conclusion is... feed well, filter "weller". As long as you maintain adequate marine snow in the water, the corals and fish will thrive and with a collection of seemingly superfluous filtering devices, you can remove residual Po4 (phosphate) & No3 (nitrate).

There is no shortage of filtration options, some more valuable than others. You must weigh the initial cost, operational cost, maintenance, convenience and residual to measure their merit. I find filter socks to be cheap and easy with little residual if you have the time to clean them at least twice a week. The bacteria removed by skimming are only the free-floating "castaways" from the exponentially larger colony of bacteria in the substrate so lower bacteria rates in the water column doesn't bother me. Sponges primarily consume bacteria so a benthic/cryptic zone would lower bacterial counts, and a skimmer limits the growth of sponges.

Bacteria is easily fostered with the addition of a carbon source such as vodka, vinegar, glucose or biodegradable polymers. In my opinion, the carbon source should be added directly to an anaerobic bacterial bed, rather than poured randomly into the water column. The danger with low nutrient systems is you deprive corals of inorganic (dissolved) nutrients. You must compensate for low inorganic nutrients by increasing organic nutrients. A partially automated system that slowly adds zooplankton and phytoplankton will make up for our mini waste water purification plants.

I have had good success with non-hatching decapsulated brine shrimp eggs, finely ground plankton, and frozen cyclops. Some people swear by oyster eggs, but I can't justify the cost.

Sorry if I came off like I was trying to redirect wind from your sails... That was not my intent.

I would have to say that you have summarized above exactly what I have found in my search over the last few years with inport vs. export. Each system reacts VERY differently and you must make adjustments as you see fit. I think this thread represents a very good aspect of a method of mimicing conditions seen in a natural environment WITH biological methods. I too cannot say 'this is the way', as I'm constantly reinventing my system and the methods I utilize for my common goal of thriving coral, fish & invert with the conditions to promote reproduction. Have I found the 'right' system yet? No...not even close. I have taken the methods from this thread & Tyree's/Borneman's methodology to create a hybrid system incorporating something from each method. The best we can do is discuss our experiences, hypothesize new ways and experiment to test these ideas. In the end, we can mimic mother nature but not replicate mother nature b/c she has 2/3rd of the globe for her canvas and we have a couple hundred gallons at best...

Happy Reefing! :wave:
 
Well that sounds a hell of a lot better than work :)

My boss is talking about sending me to get trained up to use the mass spectrometer we have in our lab. That's when it gets really fun :spin2: Actually, unless we need to use it, the mass spec is a pain in the butt to use. It is wayyyyy too sensitive and usually we end up getting more signal from the contaminents in our lab than from what we're looking for.

I'm a complete nerd. I actually enjoy my job and I'm usually a little disapointed whenever I need to stay home.

However, I'm working on designing a tiny SPS system for my desk. The display will be about 20 gallons, but I have room under my desk for about another 80 gallons worth of sump. I plan on utilizing the duplex sump concept illustrated in this thread without a skimmer or UV sterilizer. It'll be a slow go, but I'm hoping to get the sump set up before the summer and I'll let the sump condition itself for about 6 months while I add one cube daily of frozen fish food. I'm sure I'll start a build thread.

I'm not planning on going skimmerless because I'm trying to save money, but because I believe it actually may be a better way to go (especially with an oversized sump). Traditionally the azooxanthellae corals, gorgonians, and sponges have been nearly impossible to keep long-term. Based on a lot of reading and some conjecture, I suspect that removing the skimmers and relying on an oversized sump for "natural" filtration would preserve the microfauna to more natural reef levels and facilitate the keeping of species like Dendronephthya - especially if you feed almost exclusively a variety of live phyto and zoo planktons. If I can get a stable "natural" system and get good SPS growth, then I'll go the next step and try the NPS stuff.

The duplex sump concept allows you to basically cram two completely different biotopes into one tank and could potentially be of a significant benefit to NPS systems.

I'm renting a house for about the next 3-4 years until we buy our next house so my dream 180 gallon NPS system will be on hold until then. This desk system will let me try out some of my ideas in the mean time. Again, once things get rolling, I'm sure I'll start a build thread.
 
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Hey guys,
I have been out of the hobby for a while (Young kids). The wife has finally given the go ahead for a custom build, and I have been planning it for about a year (she made me sell my tanks when we moved to our new house, and is now paying me back with a longer leash since I waited until the kids are in school). I will be putting in a custom 750-1000 gal reef. I have been having a lot of fun with the technical aspects of the planning. I also own a cabinet shop and a CNC router, so some of this time has been spent building some of my filters. I love Diy. To the Point: I had been planning on incorporating a dead space under my sand bed in the main tank. I want about 4" of sand and about a 3" dead zone underneath it. I will use fiberglass window screen mesh to separate the sand from the void. The twist is, I was planning on sectioning the floor of the tank into about 6 separate zones. I was also planning on have approximately 10 to 15% of my return flow divided between them. I know that the upflow will prevent alot of anaerobic area of the sand bed, but with such a low flow, I am guessing that the water will channel and still leave anaerobic zones. I wanted to incorporated a ball-valved bulkhead into each section to allow me to flush the sections for detritus (and to see whats growing there) if I find it is necessary. I was also going to plum the sections in a manner so that I could direct pump flow to each individual section every couple of months to wash any detrital build-up in the sand up and into the tank. I thought this would be a better methode than a gravel vac, and by having the sand bed sectioned, the tank would not loose all of the benificial organisms at once allowing sections to repopulate and recover during the section rotation. My goal for the dead space was to allow a predator free environment for copepods, amphipods, and bacteria to populate and reproduce, eventually slowly migrating into the display tank to benefit the display animals. This zone is after the protein skimmer and chemical filtration. There are no devices to scrub the water of the organisms before they enter the display. I realize that the detritus that they would feed on in the sump would not be present, but I assumed there would be more than enough "stuff" in the sand bed. I also plan on automatically dosing phyto into the return, so 10 to 15% of that should go directly to that zone (to feed it?). If not utlized it would hopefully continue to flow up to the disply tank at a diffused rate. I stumbled onto this thread and the discussion finally got me to register with reef central (good job guys!). After reading this I realized that what I had incorporated was a Cryptic zone. There should be very little if any light, and it has the benefits of having the same surface area as the tank (much more than I could fit into a sump). After reading the thread I am now considering incorporating eggcrate into the void for the attachment of cryptic/benthic organisms. I would really appriciate your thoughts on this approach!
 
You guys are killing me with long winded posts that are full of interesting comments:) I open most of these posts on my phone and get buried.

I'm still happy with eggcrate as a medium. It has the right amount of void space, it doesn't trap detritus, and it's cheap and easy to find. Live rock works, but it's more for bacterial growth than invertebrates. Eggcrate plates can be easily observed and even removed as needed. The only improvement I can think of is a system that flushes out detritus. A surge system would work well for this.

As I have stated before, the Duplex system is for conservation of valuable space. If you have room for a larger system, then by all means take advantage of this resource.
 
The duplex is one of the best ideas I've come across for a natural way of nutrient export. The most significant thing I've noticed about this concept is how you incorporate the eggcrate and spread the chaeto out like an algae turf scrubber! It's like the best of both worlds and a lot more easier to maintain! The addition of aptasia/sponges/etc is neat, but not necessary. imo Very cool concept and urge people to give this a try!
 
Here is mine that i just started up. I tried usung live rock in the bottom as it is already loaded with sponges, fans, etc.

57586cf2.jpg

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Really what I'm asking is what do you think of incorporating a void under the sand bed in a display tank as long as you can flush it out?
 
Really what I'm asking is what do you think of incorporating a void under the sand bed in a display tank as long as you can flush it out?

The "Jaulbert plenum" you are asking about can have some benefit for encouraging the growth of anaerobic bacteria and benthic/cryptic inverts. Keeping it clean and knowing what is going on down there is the real challenge. It will be a limited amount of space however.
 
I'm sorry I'm not making myself very clear. I am familiar with the jaubert method, and have used it on tanks before. The key difference I'm looking at is pushing a portion of water from the return pump into the void under the sand. please reread my initial post as i think there is more there than you may have read. I don't want the plenum to be anaerobic. I want to use it as a dark place for cryptic organisms without predators, But if I put it under the sand, It would give me the greatest surface area and an area for copepod propagation with the pods being flushed up into the system.
 
I'm sorry I'm not making myself very clear. I am familiar with the jaubert method, and have used it on tanks before. The key difference I'm looking at is pushing a portion of water from the return pump into the void under the sand. please reread my initial post as i think there is more there than you may have read. I don't want the plenum to be anaerobic. I want to use it as a dark place for cryptic organisms without predators, But if I put it under the sand, It would give me the greatest surface area and an area for copepod propagation with the pods being flushed up into the system.

The same thing is accomplished with the duplex. There's no predators in a sump unless you put fish etc down there. I don't really see the benefit of the void zone..
 
Mr. Wilson

I have spent the day reading this Thread from the start, Wow, great stuff, it will fit my plans very well, I now know why I have delayed starting my project, I wasn't comfortable with the traditional, sump and Fuge designs, I had hoped for something better and I think I found it. I think I have a good understanding of your concept and I see no reason why I cannot incorprorate most of these great ideas into my design. I do have one question though, my system will have two 180g in wall display tanks (one Reef, one FOWLR), or a total 360g display to drain by CtoC overeflows to one sump. I plan on using a Reef Octopus external Skimmer sized for systems to 550g that requires a 650g feed pump. In order to match that flow with my return pump I will be returning less than a 2 to 1 ratio, to achieve a 3 to 1 flow rate I will need about 1100g's, or about twice my feed pump flow. I can feed the fuge directly from the skimmer and flow the balance in the sump to the return tank, is that what you would do? Any Ideas for a better solution to this problem. Thanks for your willingness to help so many with your obvious expertise, I am amazed at your knowledge and ability to communicate it.

Thank You................................................Stig.
 
Been a while since the last post, I wonder if this thread is still alive? If anyone cares I think I will match the feed pump to the return/circulation pump, Y the feed pump, 1/2 to the skimmer then to the return sump, and 1/2 to the fuge that will flow to the return sump. Nutrient rich water to the fuge, and water skimmed only once before return to the display. I will incorporate the Duplex Refugium concept illustrated here in this thread. While this design will not provide skimmed water directly to the refugium as recommended, it will provide the same amount of treated water in GPH as is circulated in the system. I will use a flow rate of 4X, or about 1450 GPH. If anyone has any comments or better ideas, please let me know.................................Stig
 
Been a while since the last post, I wonder if this thread is still alive? If anyone cares I think I will match the feed pump to the return/circulation pump, Y the feed pump, 1/2 to the skimmer then to the return sump, and 1/2 to the fuge that will flow to the return sump. Nutrient rich water to the fuge, and water skimmed only once before return to the display. I will incorporate the Duplex Refugium concept illustrated here in this thread. While this design will not provide skimmed water directly to the refugium as recommended, it will provide the same amount of treated water in GPH as is circulated in the system. I will use a flow rate of 4X, or about 1450 GPH. If anyone has any comments or better ideas, please let me know.................................Stig

Protein skimmers should always have a dedicated pump in order to keep flow rate dead steady. When you tee off feed lines to skimmers the water level in the skimmer fluctuates and adversely affects performance (too wet or too dry).

There is no magic number like 4 x the tank size, it depends on the skimmer feed. Now if your skimmer feed happens to be 4 x the tank volume then it is magic :)

As a general rule, filtration devices operate best at 1.5 x the volume of the tank. This assures optimum dwell time in each device. Once the water gets to your sump, it can pass through each device in succession. UV sterilizers are fed according to wattage, but if sized right, often work out to 1.5 x the tank size.
 
As far as copepod populations go, course substrate and phytoplankton seems to be the key. I doubt they consume much of the phytoplankton directly, but it seems to help with food webs.
 
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