Plenums and the wasting "option"

[barryhc]

<a href=showthread.php?s=&postid=6329126#post6329126 target=_blank>Originally posted</a> by SHIRDI
Ok, I've read all this thread. Not going to claim to understand all that is said. I don't know if my experienc is helpful.

Thank you for reading the thread from the beginning, it is a huge help to you and me. This is the only post we've gotten with direct usage information. ABSOLUTELY, it is helpful!!

I would like to read up on the Smithsonian Tank, do you have a link for that information?

I have a total of 16" from bottom of "v" to top of the graval. (all of this space is not gravel.)

How much vertical space does your "V" shape take up of the 16" total? Do you have any pictures?

Every year for the past 4 years I have added 20lbs of "GARF" Live Sand Activator to replace the subsrtate that breakes down.

20 Lbs. sounds like an awful lot, how much sand would you say comes out of the drain?

I drain 10 gal from plenum/refug every 2 to 3 months using the valve installed on bottom of refug. I didn't start to drain the plenum/refug until the tank was set up for 18 months. Ill explain later why I waited 18 months.

I have 10 mos. on my little tank, and have not wasted yet.

The material I pull out would be decribed as a thick soup with some fine sand mixed in. I find lots of worms in the soup. When I first smell the drain soup water it smells like sweet fishy dirt. (if that makes sence) After about 1 hour it begins to smell like rotten eggs-sulpher.

This is VERY-VERY interesting!! Is all of the 10 gallons thick soup, or some smaller portion of the total. tell us more about the worms, have you identified what kind they are? If not, then maybe some pictures after your next "drain".

It sounds like exposure to oxygen is initiating an intense sulphur cycle in your bucket. This again is extremely interesting.

Tell us also about the nitrate history during the first 18 mos.

Are you running rubble, sand, BB or what in the display tank?

Thank you for the post, it is very helpful indeed. and Welcome to "Plenums and Wasting". > barryhc

 

[salty joe]

Shirdi,
Great to hear from you.

Any chance you can post pics of your V system?

Thanks,

Joe

 

["Umm fish?"]

Hey Shirdi! Thanks for the info. Actually, from reading the H2S article this month it sounds like a hour in the bucket without circulation is what it takes to use up the O2 and for H2S to start to form.

It sounds like the bottom of your sandbed is a pretty happy place to be if you are getting a good smell right out of the bag (or drain ) and you have macro life down there.

Really exciting info! Thanks again!

 

["Umm fish?"]

Oh, and thanks for the durso info, Barry. It makes sense that it should drain faster if there's less air in there. Air takes up space, too.

 

[SHIRDI]

I'm glad that I took the time to read this forum. I'm a very slow reader and even slower typer. So bare with me. And my schedule is very full, so it might not be instant replies.

I don't have a camera but will try to barrow someoneââ"šÂ¬Ã¢"žÂ¢s. I'm sorta of a loner and this might be difficult.

I first became interested with the "v" design when I saw a picture of the Smithsonian refugia in Delbeek and Sprung book "The Reef Aquarium" vol1 page 157. They use turf scrubbers at the Smithsonian plus the refugia and no protein skimming. And I did not want to go that rout. I made mine just from the picture and some input from a business partner who had been behind the scene at the Smithsonian.

Sorry Iââ"šÂ¬Ã¢"žÂ¢m not very internet knowledgeable and don't know how to do quotes from other posts. So i hope you all can follow as I answer you questions. I'll try to keep the in order of posts. with that said I believe I'm on barryhc's 2nd question

The "V" is 14".

20 lbs is a lot but I add some to main tank also. At 1st I would say 30%(3gal)of the 10 gal drained material was fine sand silt, but after 6 or so drainings it is down to about 10% (1gal).

I have never any reading of nitrates in my main tank from day 3. I use Seilfet test kits and test every week. I did however find trace amounts in the refugia after purging refugia. I have always tested the main tank and the refugia separate.

I really love the rubble look. And love the Goldenhead Goby. So I Put down 2" of CarabSea Speacial Grade Reef Sand. And then slowly added over 180bs of ââ"šÂ¬Ã…"œGARF Grung +ââ"šÂ¬Ã‚. (you can only order 20lbs every 3 to 6 months.) I had someother people make orders for me to get 100 lbs to start. This Stuff if small sea shells, sand and sludge. The great sludge that gives life to so many creatures. Like starfish, copeapods, sand stirring worms, spunges and scud shrimp. I have even had small corals appear in the rubble 2-5 weeks after adding the Grunge. <----I really do believe this is why I have had such success in controlling nitrates. I place the sand under the rubble so at 1st the Gobies could not bit into the rubble eating all the creature I want to hatch and live. So slowly the Gobies found easy areas to access finer sand and began mixing the rubble and sand to make a real nice natural rubble bed.

Now for the main problem that seems to occur with this system. Oxygen bubbles form on the glass and rock during the 1st 6 months. And when I run the skimmer for more then 2 days at a time. During the 1st 6 months I do not run protein skimmers so I give Coralline algae a chance to get a strong hold. I can see air bubbles forming in the gravel of the refugia and then they are released into the water. I don't like the fact I can't run a skimmer 24/7, but I don't want baubles to start to form on corals and damage or kill them. After 7 years and still no change is occurrence of bubble when I run the skimmer. 1 of 2 things is happening.
1- I donââ"šÂ¬Ã¢"žÂ¢t have this skimmer dialed in or set up properly. I don't
believe this is the case.
2nd the skimmer being so large, and a venturi, I am over saturating the tank wih oxygen. this is more likely, I'm guessing.

The weirdest thing is everything grows fast and healthy except Mushrooms. I have Acroporas, Clavularias, Favias, Hydnophoras, tubinarias, Xenias, Sinulrias, Sun corals and even Goniopras that all thrive and get propagated and sold. But those damn mushrooms always get smaller not bigger. I guess i shouldnââ"šÂ¬Ã¢"žÂ¢t complain to much I get difficult stuff to thrive.

 

[barryhc]

I found this recently under "filtration" in the "newbies" forum.

The two most common depth filters are granular media and fiber. Sand filters are granular media. They are often used in water and wastewater treatment. In the early days of wastewater treatment in England Sir Edward Franklin introduced slow sand filters for purifying wastewater. A bed of sand of a foot or two deep was laid out over an underdrain. Wastewater flowed over the top of the filter and, as it passed through, particulate matter was trapped on the sand, mainly on the surface. As people studied such filters they found their filtration ability improved with age (something which doesn't happen with yours truly). It was found that over time microorganisms would colonize the surface of the sand. These microorganisms secrete sticky sugars and proteins to cement themselves to the sand, help catch food, and to provide a protective barrier against the environment. By having bacteria on the surface this same sticky glue closed the diameter of the pores in the sand and also provided a means to capture particles directly on the surface of the sand; this biofilm layer is called the Schmutzedecke, German for dirty skin. Now sand is too hard for most particles to penetrate but this soft biological glue allowed for particles to penetrate and stick, much like throwing darts in to a cork board. This process is called a sticky wicket in England but impaction by the rest of the world. In the mechanisms of filtration, sieving retains mainly larger particles, interception intermediate and impaction very small particles. With early slow sand filters having the dirt mainly on the top of the filter allowed them to be cleaned. Every so often a group of men would take boards and scrape off the top layer of sand. The filter was them allow to sit submerged for awhile to allow a new population of bacteria and other microorganism to grow before the filter was placed back in service. This process is called ripening the filter. In New Haven, Connecticut the water treatment plant there is one of the few in the U.S. to use slow sand filter. During testing on those filters it was also found that incoming water with organic compounds dissolved in it had markedly reduced amounts after passing through these filters. Clearly the filters had hidden benefits that we will be discussing later on in this thread.

The problem with slow sand filters are the same ones that plaque any surface filtration type. To get much output out of them we need a lot of filter surface area; slow sand filters can take up acres of grounds. To decrease the overall size the rapid sand filter, a type of depth filter, was introduced. This is the type filter generally used in water treatment plants today. Rather than a surface filter it is a depth filter with layers of gravel topped by increasingly finer size sands. Now this it the inverse of our funnel type model, the finest sand is at the top. There is a reason to do this, as I said in the first post in this thread, a depth filter is tougher to clean than a surface filter. In a rapid sand filter flow rates are several times that of slow sand and, even with the fine sand on top, particles penetrate deeper into the bed.

These finer particles, are the detritus, that is smaller than the sand particles. These will "Waste" nicely.

This appears to be information that has been around for a long time, and in my view at least, seems to support the "Gravel Membrane" concept.

Just "one more" trip to the HWS, and I'll have Joe's "Waste volume" Gizmo ready to install. REALLY!!

> Merry Christmas All !!! > barryhc

 

[BreadmanMike]

Merry Christmas Barry!
I look forward to your presence in the next BB/DSB debate.
We all just have to play nice.

 

[sradmin]

Hi, Barry, I'm still tagging along. I read with interest the quote you posted about gravel membranes, but I couldn't find the thread when I searched for filtration- too many results to sift through, not enough time!

Anyway, do you have the link? Sounds like a good read.

Merry Christmas!

 

[Paul B]

I read most of this thread, sorry I did not read it all but most of it, I will get to it. The only problems I found about the hydrallics are the holes in the manifold will clog in time, no doubt about it, but there is a simple solution. Instead of holes just substitute slits. like with a hacksaw blade. No where near as easy but slots will not clog, any sand grain will clog a hole especially when you are talking about a non maintanable, non fixable long term system.
I know a little about slots Verses holes since I have been using a reverse UG filter for three decades. I also designed many "hole" systems. I removed my UG filter plate last year for the first time in 25 years and nothing was clogged but there was a lot of detritus and sand under there which would have clogged holes in short order. I know my system is not the same as what you are proposing but water is water. I have my own ideas about the theory but I will wait on that. I also siphon water out from under the plenum (UGF) with a diatom filter, this does not remove much detritus because it is "growing" under there, in other words, it it kind of sticky. To get it out I need to push water down the tubes very fast to loosen it up. I know this will not work or be practical in your system unless you also design another tube under there to push water in while a different tube sucks it out. If the inflow and outflow rates are the same you will not push or pull much water through the sand/gravel.
Just some of my thoughts.
Paul

 

[barryhc]

Steve, here's the link to the main thread. Click the first link in the second post. Then the post you want is well down the page on page 2. It starts with the large red font .

http://reefcentral.com/forums/showthread.php?s=&threadid=166836

Much good reading in the whole thread. > barryhc

 

[sradmin]

Thanks, Barry. I've been browsing that forum, too. Waterkeeper has done a great job at organizing and condensing different filtration methods.

And his avatar of Moe just cracks me up. :lol: It's classic...

 

[WaterKeeper]

<a href=showthread.php?s=&postid=6366236#post6366236 target=_blank>Originally posted</a> by sradmin
And his avatar of Moe just cracks me up. :lol: It's classic...

Classic? Does that mean Old?

Just saw this thread but haven't the time to digest it all. Barry, are you treating the plenum void space as a suspended growth reactor? If so, using a "sludge wasting" regime as a nutrient export mechanism? Sounds interesting.

I'd spend more time following the thread but I can't do it until tomorrow.

 

[barryhc]

<a href=showthread.php?s=&postid=6367109#post6367109 target=_blank>Originally posted</a> by WaterKeeper
Classic? Does that mean Old?

Just saw this thread but haven't the time to digest it all. Barry, are you treating the plenum void space as a suspended growth reactor? If so, using a "sludge wasting" regime as a nutrient export mechanism? Sounds interesting.

I'd spend more time following the thread but I can't do it until tomorrow.

Well, you're "getting warm" at least. I think the "growth reactor" is pretty close. What you are "growing", and what "stage" it grows to, would be dependent on several factors, most especially, the frequency of the draw, along with "draw depth", and what substrate particle size and depth.

For the high frequency version, that I have been "promoting", the export is expected to be the nutrients and compounds that would eventually turn into "sludge", but wasted often enough that the sludge stage never occurs, thereby avoiding "snot" and "clumps" and clogging. That at least is the intention.

I don't know enough yet to say what the correct or "optimum" frequency, or draw depth, or particle size, or bed depth are. I have offered "models" for these factors, but they are of course, models, and are unproven. I am of course looking for feedback, input, criticism, opinion, etc. in these regards in order to learn more.

I think experimentation is the key to determining the most effective "set-up", and that is surely going to take some time. Still, discussions about bacterial populations and their "fluxing" can only be helpful to the endeavor. What is being done, and investigated in "water treatment", is likely to be very pertinent to understanding bacteria's reactions to "fluxing the oxygen level".

I tend heavily toward frequent wasting, and the info. above is "geared" toward that version. As has been shown by Shirdi's posts above however, occasional wasting is likely to be a quite valid version of this concept, and needs to be pursued with equal endeavor.

Many posters here are interested in the occasional version, and I support their efforts. The mechanics and variables however, will surely vary.

By the way WaterKeeper, "Classic" often times means "of great value" and "worthy" of Preservation ( Doop! ) and "showing off"!!!! :lol: :lol:

Thanks for visiting, and come again. > barryhc

 

[ethanriley]

After haviing read through all of the notes I am curious as to why you are concerned about perserving the anerobic/aerobic gradients when you purge? I feel though I could be wrong the majority of bacteria existing in the anerobic environment can withstand the presence of oxygen. I like the manifold design however i think you will have to add multiple intakes to ensure an equal draw.

 

[barryhc]

<a href=showthread.php?s=&postid=6422531#post6422531 target=_blank>Originally posted</a> by ethanriley
After haviing read through all of the notes I am curious as to why you are concerned about perserving the anerobic/aerobic gradients when you purge? I feel though I could be wrong the majority of bacteria existing in the anerobic environment can withstand the presence of oxygen.

Whether or not the Anaerobic bacteria can "withstand or survive", the introduction of oxygen into their environment, would have a lot to do with the "time-span" of that exposure. "Obligate Anaerobic bacteria", cannot withstand this exposure for very long, although I have not yet found what that time frame is.

I like the manifold design however i think you will have to add multiple intakes to ensure an equal draw.

The last 55 gal. design has 4 intakes that feed into a single "oversized drain-tube". Have you seen that? It is in my gallery.

Thanks for posting here, and stay with us. > barryhc

 

[menard]

Barry, the mannifold was brilliant.In the past I have this wild idea in my mind, but I never find the time to do it. I thougt about using acrylic cannals sloping down at one end of the tank,drilled and gate valve, slow drip over the course of 1 mo. I set up my 1st plenum back in1996 until this date. I pulled the plenum in my 125 when I up graded to 300, yr. 2000. This time I add the 3rd screen, I figure I would siphon the top layer of the sand every 5 to 10yrs. and replace it w/ new live sand. Actually the 1st one aint dirty at all as long as the tank is functioning correctly. BALANCE, so to speak. __________________ PEACE

 

[barryhc]

Thanks for joining in Menard, can you tell us more about the system you installrd in the 300 gal. tank, and how it is doing. full descriptions of manifolding, fish animals substrate, support filters and maintanence are very helpful.

Thanks again, > barryhc

 

[menard]

<a href=showthread.php?s=&postid=6451282#post6451282 target=_blank>Originally posted</a> by barryhc
Thanks for joining in Menard, can you tell us more about the system you installrd in the 300 gal. tank, and how it is doing. full descriptions of manifolding, fish animals substrate, support filters and maintanence are very helpful.

Thanks again, > barryhc

Barry,the whole acrylic cannal mannifold pitch on the side the tankand gate valve,still an idea, never get around to do it. Put up on hold.Insted ,the 125 that I used to have, already in service w/ plenum builted in it.Same concept, old school. That one working perfectly, until I move everything to 300.The only difference I did was, adding that 3rd. screen, on top the 1" special grade reef sand. I figure I would siphon this every 5 yrs or 10 yrs. depending on the look on the animals. Just good husbandry. Now the tank is aproaching 6yrs this Feb.things are great.In fact I discontinue the use of PROTEIN SKIMMING for 8 mos. now, and I dont see any difference w/ my water quality, corals grows the same,skimmer or no skimmer. Like I said before, balance is the key.And I know you agree on me on that_____________________PEACE

 

[joefish]

I can't beleive you made me look for it .:mad2:


Now it's gonna take a seperate night to read it , all 16 pgs.:lol:

 

[barryhc]

<a href=showthread.php?s=&postid=6478178#post6478178 target=_blank>Originally posted</a> by joefish
Now it's gonna take a seperate night to read it , all 16 pgs.:lol:

Which night is that going to be? :lol:

> barryhc