Jaubert Plenum

[NaH2O]

Originally posted by Curtswearing
I think a lot of the above is very interesting. I still see the need for a light bioload or a very large plenum.

I'm not trying to be a pain....just trying to get a handle on the situation.

I think that Maxx's idea of 2 remote plenums is an interesting one. IMO, this would almost be the same as a very large plenum.

You aren't being a pain....just helping with the discussion!

[mojoreef]

Alright we got some good questions, let see if we can work through them.
Nick on the two plenum system, yes that can be done and can be done just as you discribe it. Where I am leaning is to try to bring about a system where total reakdown is not needed. We have lined out most of the problems that sand substraights have and I think have worked past them. if we excersize the proper setup and miantence cant we gat past the breakdown, if not wat are you seeing that requires it? tell me what you think is going to cause the need for a complete redo.

Curt keep throwing in the questions, alot of times we dont see everything and all input helps to do this.

I think maybe I am looking at this a little different then you and maybe others. To me I am looking at this set up as a compliment to the system, not a replacement of reactor or skimmers and so on. A sand substraight filter can offer denitrification and a source of larval and microscopic life. I am looking at it as a source of the above to be added to a reef system, if given the choice between this and a refugium using macro algae I would choose this, IMHO.
Curt on the fusing, it is the critters that stop this fusing, thier stirring of the bed does not allow it. If a failure occurs as you discribe it would not fuse the particles over night for sure.
On the phosphate being to much of a risk, you may very well be right. How do all you folks feel about the phosphate binding in the sand particles, do u feel it is to big an obsticle to over come??

Mike

[Curtswearing]

Originally posted by mojoreef
I think maybe I am looking at this a little different then you and maybe others. To me I am looking at this set up as a compliment to the system, not a replacement of reactor or skimmers and so on.

That changes my comfort level substantially.

On the phosphate being to much of a risk, you may very well be right. How do all you folks feel about the phosphate binding in the sand particles, do u feel it is to big an obsticle to over come??

I'm very interested in discussing this.

[mojoreef]

Well Curt??? discuss, lol.
For me the phosphates locked up in the substriaghts can be controlled to an easy pont where thier influence will be minimal IMHO. The main concer are two fold when it comes to Phosphates, inorganic forms that are introduced to the tank and those that are locke into biological organics (these types resided in the bed) controling them is a major concern.

Mike

[Curtswearing]

I have a number of comments but I'm stuck at work. I have some thoughts and some questions. However, I have to get to them tonight.

[Cougra]

Is there any determined surfacearea to bioload ratio? How would we be able to determine the size this remote plenum needs to be?

and in a remote location we allow fo no light, no light means no algae, which means the phosphate stays in animal form and can be exported via the suction (in animal form I am talking bacteria only).

I think I missunderstood this previously, I know that you needed to minimalize the light in the lower layers, but I for some reason I didn't realise that we weren't adding any sort of light to the plenum. This would make the system much more economical since you don't need additional electricity to run it and replacement bulbs.

How deep does the water ON TOP of the plenum need to be? would you be able to get away withmerely one or two inches of water to basically cover just the plenums substrate material or does it need to be deeper? This would also allow you to be able to stack a couple systems ontop of one leaving a couple inches head room for access and airflow, so you could utilize a minimal amount of space for additional surface area. It would also keep the water well oxygenated since there is a larger surface area to volume ratio.

[ScottT1980]

How deep does the water ON TOP of the plenum need to be? would you be able to get away withmerely one or two inches of water to basically cover just the plenums substrate material or does it need to be deeper? This would also allow you to be able to stack a couple systems ontop of one leaving a couple inches head room for access and airflow, so you could utilize a minimal amount of space for additional surface area. It would also keep the water well oxygenated since there is a larger surface area to volume ratio.

It seems to me that this would be even more efficient. If you are constantly running a "thin" layer of water over the plenum, it seems that filtration would occur more readily as opposed to a large volume of water, most of which will not come into immediate contact with the sandbed.

I think I missunderstood this previously, I know that you needed to minimalize the light in the lower layers, but I for some reason I didn't realise that we weren't adding any sort of light to the plenum. This would make the system much more economical since you don't need additional electricity to run it and replacement bulbs.

It seems to me that light would be needed for the system on top of the plenum. The reason being that the microinverts/nematodes/insert critter name here are dependent on some sort of photoperiod (but hey, I do the opposite keeping ym fuge lite 24/7 so perhaps the opposite can be done, I just know many animals, even the lower ones, have metabolic cycles dependent on photoperiod). I could easily be wrong, just a thought. As for light to the plenum, that is very easy to handle with or without light on top by just ensuring sand surrounds the entire thing...

Sorry, I am sort of in and out of this thread so I forget what has already been mentioned. Just some thoughts...

I really like the low water depth plenum idea though, surious as to what others may think.

Take er easy
Scott T.

[Curtswearing]

I have read of people who only run a couple of centimeters of water over the top of the substrate. This seems more efficient to me as well. Michelle your point about the oxygen is well taken. That possibly would have an impact on my concern with CO2 dropping the pH levels. What do you guys think?

Sorry I keep popping in at out at irregular times.....I want to know what is going on but I have a bunch of meetings today.

[Maxx]

Nick on the two plenum system, yes that can be done and can be done just as you discribe it. Where I am leaning is to try to bring about a system where total reakdown is not needed. We have lined out most of the problems that sand substraights have and I think have worked past them. if we excersize the proper setup and miantence cant we gat past the breakdown, if not wat are you seeing that requires it? tell me what you think is going to cause the need for a complete redo.

Mike,
Total breakdown was meant as a last resort type dealie... I can see that gravel washing would more than sufice if done on a yearly basis. Otherwise I'm quite certain that the drain/pump system you mentioned, used in conjunction w/ vigorous stirring on occasion, would be more than enough. For the purposes of this system, I'm looking at the gravel washing as part of the maintenance to be done a regular basis, albeit with long intervals between. Or are you saying that this is uneccessary and potentially harmful to the population of the main/display tank over all?

This would also allow you to be able to stack a couple systems ontop of one leaving a couple inches head room for access and airflow, so you could utilize a minimal amount of space for additional surface area.

Okay granted I'm not the smartest guy here, (that house monkey thing is only partially a joke!) but are you suggesting multiple plenums in one container? how would this happen? Or are we discussing multiple shallow water plenums stacked up in seperate containers some where....like a rack or shelves er something? This makes more sense to me.

It seems to me that this would be even more efficient. If you are constantly running a "thin" layer of water over the plenum, it seems that filtration would occur more readily as opposed to a large volume of water, most of which will not come into immediate contact with the sandbed.

I thought that part of what made plenums work was the water pressure aspect which "pushed water through the plenum, (albeit slowly) and allowed denitrification to occur that way?

my concern with CO2 dropping the pH levels.

Umm I thought that the lower PH water was sposed to stay beneath the plenum? If thats the case, why are we worried about it? The only way Co2 would get free in the tank (from a plenum)and lower pH is if it was disturbed and the lower PH water was released. Taking the Plenum assembly (why not there's more than one in this discussion, we might as well call it an assembly...) off line to do any maintenance, and going w/ Mikes Plumbing /flush solution should adequately prevent that from happening. unless I've missed a post here somewhere and didnt catch the part where we need to be worried about low PH/ Co2 escaping into the aquarium from the plenum? As far as disturbing the plenum for cleaning and releasing the low ph/co2 monster, just have a plan for when you bring the plenum back on line w/ the rest of the system....run the effluent, (remote set up remember?) through a pitcher like Mike does for his Calcium reactor, (air stone inside pitcher off gasses the excess CO2), run it through your skimmer for a bit...
just some thoughts
Nick

[mojoreef]

Yep thats the concept folks. The thing we need to concider is contact time, the more the better, also plumbing straight form the tank or something close is also a concideration so we make sure the detritus hits the bed. So in what I was talking about, yep about 3 inches or so should be fine (it will also help with particle fall out). .
On the lighting I was thinking black no light. The bacteria required for processing does not require it. The lack of light breaks the phosphate cycle (organic wise) by not allowing the vegitation part of the cycle to be had. So instead of the bacteria dieing (releasing their bound phosphate) they die and the phosphate sinks with the carcusses instead of fueling the algae bloom. Then we give the whole thing a suck and life goes on.

"Its the solent Green facter" lol

Mike

[mojoreef]

Sorry Nick you beat me to the reply button
Nick I am not sure what the washing is supposed to do? I need some help on that??

I thought that part of what made plenums work was the water pressure aspect which "pushed water through the plenum, (albeit slowly) and allowed denitrification to occur that way?

Not to fast a flow, but pressure wise no. The nutrients and so on are migrated down by critter and bacterial action...and water flow.
Ok on the co2. If a power outage occurs the plenum (water, bed, not the plenum zone) will take a hit and co2 will be in the water, but also you whole tank will be experencing the same thing, but probibly a heck of a lot more. When the power goes out and the lights turn off, photosynthesis stop, oxygen from the surface stops, basically all oxygen input stops. But you critters (from fish to corals to worms) dont hold thier breathe, they keep sucking it up and exhaling co2. So where thier is a bioload expect co2 input.
On the plenum zone itself if you dont disturb it the water will not magically raise and pollute the system. If one times thier stirring with the sucking of the plenum, I also dont see any pollution coming from that source either. Plus you can just disconnect it from the main.

Mike

[Maxx]

Nick I am not sure what the washing is supposed to do? I need some help on that??

I was thinking detritus removal....crap sinks and w/ a system designed to pull stuff through it, your gonna get deep crap that needs to go....That was my line of thinking. Am I wrong?

If one times thier stirring with the sucking of the plenum, I also dont see any pollution coming from that source either. Plus you can just disconnect it from the main.

Uhhh...how is this different from gravel washing?

[mojoreef]

Ok thats why I asked. I was thinking you were talking about removing the particles and taking a hose to them or something. So I think we are on the same page.

mike

[Maxx]

Cool, I thought maybe I was being set up for the butt of an enormous joke....not that I mind, I just wanna hear the punch line...
Nick

[Cosmic]

Great thread you guys have going here. Sorry I'm so late in jumping in (seems to be my trend these days ), but I did have a few thoughts on this whole idea you have concieved.

Firstly, you mention using larger grain substrate for a more oxygenated flow through in the substrate. This is supposed to help with clogging mainly.
Now, with a fast flow rate going through your plenum area, what is going to make that piece of detritus decide to STAY in the plenum and not be returned to some other part of the system?

I don't know, but my concept of your plan is a modified undergravel filter, with a reversible powerhead to remove the buildup? Weren't we there about 10 years ago?

I haven't done any current research, but from what I recall, the reason the grains were the size and depths they were was to control the flow of water through your bed. Making use of larger particles means either a DEEPER bed than before, or a hit on denitrification.

Another problem I might foresee is the "drain" (whatever you opt to use) trying to suck more than the bed is going to allow through it. Remember, too much flow and we don't have any denitrification occuring, meaning less water (flow) through the bed also. Is it going to be able to pull 700 gph through it?? I think your suction problem might again pop up here, possibly.

I understand what you are trying to accomplish, but I'm not sure that I agree with the methods of achieving it. Flow rate is critical to the success of denitrification, and the way I see it now, you're just re-designing the UG filter.

Ok, you can take your shots now

Cos