Plenums and the wasting "option"

[barryhc]

So, "Umm fish?", are you still in the "Low Frequency" category of interest?

It is perfectly fine, if you are, but I think there will be differences between "High" and "Low" frequency "wasting", and it would be beneficial to all concerned, if the type of "wasting" that you are developing is known, for clarity of communications.

Nice to see you back, and Thanks, > barryhc

 

[barryhc]

By the way Doug, I got a look at your gallery, and that in the wall implementation is really really nice. Is that about a 150 gal.?

Thanks again, > barryhc

 

[DougSupreme]

Doug, that looks a fairly large tank. what size is it?

How many holes, just out of curiosity? How did you cover the plenum?

Have you been running the system, and can you report any results?

Welcome to the thread, and thanks for posting! > barryhc

It is a Perfecto 120G 5'L x 18"W

I have no idea how many holes, I suppose I could figure the number, I seem to remember that the holes were 3" apart. I simply wrapped the piping in landscape tarp( the fabric kind) and poured the southdown on top of that to a depth of about 4.5"


I have had the system up and running for over year. Unfortunately, I haven't really been recording any results up to this point, and my tank is scheduled to be torn down for a move in the next two weeks. When we move to the new house, I plan on setting the tank back up, so I should be able to record results .

 

["Umm fish?"]

Nice to be back . I had to run off and be sick with my child and then have a birthday . Sucks getting old.

I am still in the "Low Frequency" category. I just think DSBs do what they do very, very well for a certain length of time. So, I just can't see screwing around with anything on a regular basis. Depending on what I find when I start sucking out of the bottom of the bed, I may pull about an inch off the bottom of the tank every 6 months or so and see how it goes.

I'll be really interested to see how the tank parameters change with each pull.

I have a theory, though. Tell me what you think. I think that no matter how we try we are going to get some channeling in our wasting. Further, I think that the anaerobic bacteria in these areas will survive our draws with no problems (since the water is channeling around them). And I think that these bacteria will very quickly re-colonate the rest of the SB after the draw, thus mitigating the parameter spikes that might occur.

I guess I'd better get experimenting.

But that's why I remain in the "Low Frequency/Higher Volume" category. So, what do you think?

So, "Umm fish?", are you still in the "Low Frequency" category of interest?

It is perfectly fine, if you are, but I think there will be differences between "High" and "Low" frequency "wasting", and it would be beneficial to all concerned, if the type of "wasting" that you are developing is known, for clarity of communications.

Nice to see you back, and Thanks, > barryhc

 

[barryhc]

voodoody, let's get back into some of these "zones" again. You had said that Hawke might have had a problem with "losing" his "anaerobic zone".

I'm not sure, that I want to lose it either, but, let's be very careful about calling a "zone" either "anaerobic", or "anoxic".

I don't think that you have made any errors regarding these terms, but I have seen them used "interchangably", or even worse, "in reverse", on many occasions.

This can lead to much confusion, and then controversy, based on miscommunication, and not misconception, both of which lead to most of the controversy.

Let's try to keep everybody straight about "Anaerobic" and "Anoxic" areas, and bacterial populations, as we proceed.

Now, about this "Anaerobic zone", I'm not sure why we need it, I'll admit. So as we try to explain its importance, let's try to keep the correct meaning ( or interpretaion ) of Anaerobic and Anoxic in mind, at least so that "I" won't get confused.

This should be beneficial to the rest of "us" as well.

You, "Kbmdale", and "CaptiveReef", at least, seem to be on the same page here, and maybe we can now get into the "functionalities" of these "zones", without getting lost in misunderstood terminology.

So, again, what is the Anaerobic ( VS Anoxic ) activities, that we are wanting to preserve, in a "wasting plenum"?

Sorry about the "long-windedness" here, but I really do want to keep this thread "educational", if not "very much more".

Thanks again, voodoody! > barryhc

 

[Obi-dad]

I am trying a different version of this, using the cpvc piping but with an SSB instead of a DSB. I have a DSB in my fuge, and like the looks of a sandbed, but don't want to accumulate crap in the sandbed (pun intended). So I have this drain system to hopefully remove some of the crap periodically. I don't have to worry about the anaerobic layer, because I don't have one to being with. The tank has only been up for 6 months, so hasn't really accumulated much stuff in the sand. My nitrates and phosphates are not measurable, and I don't have an algae problem (but I have a lot of chaeto in the fuge that grows quickly).

I'm not sure what frequency/qty I will drain yet. I have a few layers of weed preventer plastic around the pipes, and use Southdown sand, so I may not get the flow necessary, and it may still channel, but my only purpose is to flush water through, not to try and maintain an anaerobic layer, so it should be easier than the ones trying this with DSBs. Even if it doesn't work at all it was cheap to try, and shouldn't hurt anything.

 

[barryhc]

It is a Perfecto 120G 5'L x 18"W

I have no idea how many holes, I suppose I could figure the number, I seem to remember that the holes were 3" apart. I simply wrapped the piping in landscape tarp( the fabric kind) and poured the southdown on top of that to a depth of about 4.5"


I have had the system up and running for over year. Unfortunately, I haven't really been recording any results up to this point, and my tank is scheduled to be torn down for a move in the next two weeks. When we move to the new house, I plan on setting the tank back up, so I should be able to record results .

Doug, "we" have a really great opportunity here, to see what happens during a "teardown" for one thing, and I wish you the best during the move.

You should have noted, that I am very concerned about "fabric", or anything, that even "vaguely" represents a "membrane".

Keep us with us here, in preperation for your "reinstallation".

Thanks > barryhc

 

[barryhc]

Nice to be back . I had to run off and be sick with my child and then have a birthday . Sucks getting old.

But it's great getting to be at birthdays and love your child!

I am still in the "Low Frequency" category. I just think DSBs do what they do very, very well for a certain length of time. So, I just can't see screwing around with anything on a regular basis. Depending on what I find when I start sucking out of the bottom of the bed, I may pull about an inch off the bottom of the tank every 6 months or so and see how it goes.

Sand beds might be able to do what they do "even better".

The 1" every 6 mos. does not sound the least bit severe, or "problematic".

I have a theory, though. Tell me what you think. I think that no matter how we try we are going to get some channeling in our wasting..

I agree, but I have been doing what I can to reduce this "channeling" to a "practical" level.

Further, I think that the anaerobic bacteria in these areas will survive our draws with no problems (since the water is channeling around them). And I think that these bacteria will very quickly re-colonate the rest of the SB after the draw, thus mitigating the parameter spikes that might occur.

That would be true, "if ", the "channeling" was that "severe", and, I am counting on exactly that perception to be true, in the "upper layer" of "my" ( or "the" ) "High Frequency" version.

I am also counting on something different to occur, in the "lower level" that I have described as the "substrate model" for "High Frequency" wasting.

You see, we can all be winners here.

I guess I'd better get experimenting.

I think so, and myself as well. I think "voodoody" is about ready as well.

You might be onto something, "Fish"!

That's what I think, and thanks again > barryhc

 

[barryhc]

I am trying a different version of this, using the cpvc piping but with an SSB instead of a DSB. I have a DSB in my fuge, and like the looks of a sandbed, but don't want to accumulate crap in the sandbed (pun intended). So I have this drain system to hopefully remove some of the crap periodically. I don't have to worry about the anaerobic layer, because I don't have one to being with. The tank has only been up for 6 months, so hasn't really accumulated much stuff in the sand. My nitrates and phosphates are not measurable, and I don't have an algae problem (but I have a lot of chaeto in the fuge that grows quickly).

I'm not sure what frequency/qty I will drain yet. I have a few layers of weed preventer plastic around the pipes, and use Southdown sand, so I may not get the flow necessary, and it may still channel, but my only purpose is to flush water through, not to try and maintain an anaerobic layer, so it should be easier than the ones trying this with DSBs. Even if it doesn't work at all it was cheap to try, and shouldn't hurt anything.

For your intended purpose, as you state it here, I think that your reasoning is fairly "sound", however, I will continue to state, that whatever the purpose, anything like a "membrane" will "clog", and "channel", so if you want to avoid "clogging", I have recommended a "model" that will not suffer from this.

Thanks for posting Obi-Dad, barryhc

 

[wrasselover]

Interesting rehash of an old thread. About a year ago I contacted Hawke privately and got a response. He eventually stopped using his plenum system and went bare bottom. He said he reached a very simple conclusion. A plenum system could be made to work, but why treat waste in the tank, and be at risk of a biological over load and upset, when it is easier to design a system to remove the waste to start, and eliminate the major biological load that it causes.

I think he asked me something like....would you build a compost toilet in your house when it is cheaper and easier to flush a standard toilet. ?

 

[barryhc]

Interesting rehash of an old thread. About a year ago on contacted Hawke privately and got a response. He eventually stopped using his plenum system and went bare bottom. He said he reached a very simple conclusion. A plenum system could be made to work, but why treat waste in the tank, and be at risk of a biological over load and upset, when it is easier to design a system to remove the waste to start, and eliminate the major biological load that it causes. If you get your tap water from a commercial water system, that water is treated to make sure it's safe for human consumption. The water is cleaned, and filtered. Then, chemicals are added to the water to prevent anything harmful from growing in the water while it's in the pipe leading to your home. Until recently, most water treatment facilities used Chlorine to kill off any organisms in the water. The small dose of chlorine is safe to drink, but many people notice the slight chlorine odor. One problem water treatment plants have with chlorine is that it's unstable, and easily dissipated from the water. This means that the treatment plants need to put in higher levels of chlorine, so that they can be sure that some will remain in the water when it reaches your home. Recently, water systems have started treating tap water with chloramine instead of chlorine. Chloramine is a combination of chlorine and ammonia. It's much more stable than chlorine. It won't dissipate from the water as easily, and it isn't as likely to combine with other chemicals. But, chloramine isn't as good at killing off the microorganisms in the water as chlorine, so higher levels of chloramine are often used. Typically, water treatment plants use about 1 ppm of chloramine.

All this hard work and chemistry is important to keep people healthy. But, the same chemicals which keep people safe can be VERY toxic to fish. Adding tap water with chlorine or chloramine to a tank can kill off fish quickly. It can also kill off the bio-filter bacteria that keep your tank healthy and happy. So, this water must be made safe for the fish and tank. How do we do this? There are several common approaches, and their effectiveness varies depending on whether your local water treatment plant uses chlorine or chloramine. If you don't know which your water system uses, ask them.

I think he asked me something like....would you build a compost toilet in your house when it is cheaper and easier to flush a standard toilet. ?

Well now, "Wrasselover", you have had your "say".

Have you read this thread?

Who is "he"?

A "DSB" is a standard toilet. "We" are working "here", on "flushing it"!

So, what is your point?

> barryhc

 

[DougSupreme]

not to flame you, wrasselover, but what does anything in your post have to do with this thread? The whole middle of your post pertains to treatment of drinking water. The last statement where you paraphrase Hawke is pertinent...and accurate. BUT, we are trying to find ways to improve the efficiency of a sandbed, not remove it. Please don't think I'm trying to start something. I just think we need to stay focused in order to make any progress.

 

[wrasselover]

My orginal post contained a cut and paste error....... much shorter version reposted.

All I was doing was restating what hawke said to me on the topic.

 

[DougSupreme]

sorry, I didn't get the truncated version. Sorry for the negative post.

 

[barryhc]

By the way folks, I have not mentioned this previously, because I want to get the "logistics, of this "working", but I do not think that any "critters" are necessary, to make this system work, "necessarily". ( just bacteria )

Those who are trying to put a DSB over a plenum, may need this. I believe that it can work just fine for someone, with no "critters" at all, but the "substrate" selection for this will probably not be "DSB".

I prefer to have critters in the "upper level" of the substrate, and that is why I'm looking into "plenum wasting" to begin with.

I want the critters, and the substrate that they require. That's my reason anyway.

Thanks all, > barryhc

 

[voodoody]

barryhc,
conversion of amonia to nitrate is a process performed by aerobic bacteria (those that utilize oxygen in their metabolic pathways). The physical location of these bacteria might be considered an aerobic zone. This can occur anywhere, not just the top layer of a DSB (e.g. trickle filters, bioballs etc). Further conversion to nitrite and nitrogen (denitrification) is performed by anaerobic bacteria. The physical location of these bacteria might be considered an anoxic or anaerobic zone. I believe these terms can be used interchangeably. Some anaerobic bacteria are facultative (can use oxygen in their metabolic pathways if oxygen is present) and some are obligate anaerobes (cannot use oxygen ever and may actually sustain injury from prolonged exposure).
voodoody

 

[barryhc]

barryhc,
conversion of amonia to nitrate is a process performed by aerobic bacteria (those that utilize oxygen in their metabolic pathways). The physical location of these bacteria might be considered an aerobic zone.

I thought that these Aerobic bacteria were converting to Nitrite, and then Nitrate. Are you sure that this not a "typo"?

This can occur anywhere, not just the top layer of a DSB (e.g. trickle filters, bioballs etc). Further conversion to nitrite and nitrogen (denitrification) is performed by anaerobic bacteria.

Same as above. "TYPO"? Or, are you saying , "back to Nitrite"

The physical location of these bacteria might be considered an anoxic or anaerobic zone. I believe these terms can be used interchangeably.

I'm not so sure about that. We need to be careful here.

Some anaerobic bacteria are facultative (can use oxygen in their metabolic pathways if oxygen is present) and some are obligate anaerobes (cannot use oxygen ever and may actually sustain injury from prolonged exposure).
voodoody

That part I understand. So some "
Anaerobes" can become "faulative", in an "Anoxic" environment.

I thought, that you had stated that oxygen "is not toxic" to Anaerobic bacteria.

Still, what is the function that we want to maintain in the Anaerobic zone, with Anaerobic bacteria?

I thought we were dealing with Hydrogen Sulfide, and low pH Phosphate "re-solution", in the "lower" Anaerobic zone of the substrate.

Have I fallen off my stool? > barryhc

 

[barryhc]

Some anaerobic bacteria are facultative (can use oxygen in their metabolic pathways if oxygen is present) and some are obligate anaerobes (cannot use oxygen ever and may actually sustain injury from prolonged exposure).
voodoody

I'm still particularly interested, with the "sustained injury", and the definition of "prolonged exposure". This is what I would hope to avoid with carefully controlled "draw depth" and "bacterial recovery time".

Thanks voodoody, let's work through this. > barryhc

 

[Obi-dad]

... but why treat waste in the tank, and be at risk of a biological over load and upset, when it is easier to design a system to remove the waste to start, and eliminate the major biological load that it causes...

What many BB'ers fail to realize is that many people like the looks of sand. BB is not a very good option if you want sand. It seems like the BB'ers keep trying to convert people who want sand. I understand that BB is an easier way of keeping the tank clean. But I don't need the easier path.

And for anyone considering putting a drain in the sandbed, you don't need to worry about all the anaerobic discussion if you are only doing an SSB, not a DSB. IMO, a good option to DSB in the dispaly tank is to have a DSB in a fuge (or even a bucket like Anthony Calfo suggests), and is much easier to change out later. This way you don't have to do a balancing act with maintaining anaerobic layers with the drain system.

 

["Umm fish?"]

Not only that, DSBs are very good at what they do: they perform the nitrogen cycle all the way to getting the nitrates out of the system. They do bind up free phosphorus, but they don't complete a phos cycle. So, eventually they will fill with phos. And that's fine. Accept what they do very well, praise what they do very well, and let's find some way to work with their deficiencies. That's my battle cry....