Phosphate build up

[cwcross]

Lets take this and transpose it into our tanks and say a dsb. With the production of end product detritus and byproducts in a sediment bed the anaerobic regions will begin to fill and clog with products that can not be used.

Yes, that is what we are really talking about anyway.

Yes, I have heard this theory and do not buy it. Neither did the microbiologists I spoke with. Granted that the end sediment will go to the bottom of the bed and be un-usable for food after being completely utilized. However, this should basically become humic type material and provide further substrate for additional bacteria to grow.

Since the limitations of area do play, the bottom and sides of the tank will put a limit on what the sediment can sink. The only regoin left to go, is up into the aerobic zone. This will eventually lead to that region going anaerobic also and the bed losing its ability to perform nitrification.

I nearly agree with this also but not quite. I believe the bed's natural balance of various bacteria will become out of balance and not function very effectively as you state. However, anaerobic bacteria would not survive in an environment in which too much oxygen is present, such as near the surface levels. As the overcrowded aneorobic bacteria are pushed upwards, they will die off and release their nutrients into the water column at a much increased rate.

I wouldnt say crash, more like it losses it abilty to filter and begins to export raw nutrients.

a matter of semantics. I'm sure you are correct here.

I dont think it would be that easy. the overloaded flask would migrate some bacteria which would bloom to meet the available food, but I would believe the vast majority would remain in the overloaded flask and basically cycle themselves out of existance.

All living populations will migrate given the correct conditions. This example is very difficult to make accurate if one takes it too literally. However, if we can arrange a system in which nutrients are added at such a rate that the population can not expand (nutrient limited) and there is available space, then eventually the bacteria will spread to fill the space homogeneously.

There is no mechanism to keep the bacteria in a single side of the tank and many mechanisms to cause them to migrate. For instance, the overcrowding on the first side and the resulting skew of the ideal ratios of bacteria you speak of above will lead to poor competition with the newly formed colonies on the fresh side because the bed is not functioning very effectively. The bateria on the new side, however, will grow very effectively as they absorb the nutrients released into the water column from the dying bacteria on the first side. Over time if the entire colony remains nutrient limited, then the bacteria will spread until competition between the two sides are equal. I can't think of a single mechanism that would lead to them staying on one side.

Way to risky. With the bed in a constant state of flux through out it, you are running the risk of unleshing a ton of nutrients in various stages of reduction, also by the time you got to that point you would have a large population of Sulfate reducing bacteria, subjecting you precious critters to the chance of releasing that is really rolling the dice.

Granted this could be risky if not done correctly and one waited until the bed was nearly saturated. However, by isolating the remote bed from the top tank, changing a fraction of the substrate very carefully, and then doing a complete water change in the remote tank, letting it sit for overnight with an air sparge, maybe doing another complete water change the next day and then sparging again overnight. I would bet my tank contents that the remote tank could be brought back online and re-connected even if the bed were nearly exhausted. However, I haven't never done it so...???

Also, if one were to attempt this, it is not something that should be done after the sandbed is near saturated. I would think it should be done as a regular and frequent part of maintenance. Then the risk would be greatly reduced. However the other option would be to change out the entire bed. The only downside is that you lose all the infauna and biological processing for a month or so if you do this.

Ok lets turn this around a tad. By taking out small sections of the DSB what is it that you are getting rid of?? (list the substances and what they are attached to).

Mike

You are exporting nutrient compounds contained in the bacteria and infauna as well as metals and toxins bound to the substrate along with much of their waste material. By providing an effective export mechanism for phosphate, and other problematical regime 3 compounds which are not effectively removed by water changes, this should theoretically stabilize phosphate concentrations in the system to some equilibrium level rather than allowing them to accumlate until the bed is saturated.

I imagine it acting as a dilution of the bacteria in the bed. If I were to replace 1 cup of mud each week, I have a very high degree of confidence that the bed will remain effective indefinitely or at the least much much longer than otherwise and that my infauna and biological processing power would remain effective. I just need to buy a new bag of mud and test the concept. :shock:

Sincerely...Collin

 

[cwcross]

Ahh the remote DSB theory. Some folks put this question to Dr. Ron and Rob T. They both seem to dismiss the notion as self defeating.

I Don't agree with them at all.

Lets look at this one for a second.
A sediment filter is only as good as the population of the correct bacteria that inhabits it. Its not a function of the size of the bed, but of the ammount of reducing bacteria it has. If a bed is not fed it will not have any bacteria (thats can be seen in real life on the sand that surrounds reefs, very few larger critters and very low bacteria populations), you basically just have an ammount of sand. So in order to keep a remote DSB functional as a filter it must be fed,[/quote]

Yes, I agree

now being remote it is going to be a whole lot less efficient then one that is in the tank itself.

don't agree

The though being that the in tank DSB will eventually get the vast ammount of the food it needs through food landing on it.

Not if you don't have one in the main tank

In the remote unit, it will not get the same ammount, (its going to be hard to get all of it out and into the remote) but I guess with some tricky plumbing you might be able to get 60%?? not sure.[\quote]

If that is true then 60% is plenty

Now the second problem is in contact time. In the tank contact time is not an issue (in most cases), but in a sump or remote you really need to slow the water down, so lets say 100 gph?? not sure but it would have to be really slow. So now how does that effect the ammount of bioload a remote could handle. I think mud systems fall into this catagory also.

just some thoughts.

Mike

Here I disagree. Contact time will have nothing to do with nutrient filtering capacity. Too much flow is bad for infauna and of course you don't want to blast things off the glass and such, but the filtering will remain effective for any soluble materials such as Nitrate etc. My system has about 400 gph going through it.

You should tell the theory above to the culerpa exploding out of my refugium and the swarms of pods and worms in there. Also, when I blow my detrius off the rocks and sand bed, the refugium gets plenty of debris.

 

[mojoreef]

Collin I do love talking with you.

Yes, I have heard this theory and do not buy it. Neither did the microbiologists I spoke with. Granted that the end sediment will go to the bottom of the bed and be un-usable for food after being completely utilized. However, this should basically become humic type material and provide further substrate for additional bacteria to grow.

Ok, lets look a little deeper. Simple stuff first.
>Chunk of food hits the bed and is brought down to the bottom of the bed through critter movement. In this area thier are no bacteria that can use it as it is not redued to a food source they can use. The bacteria that could reduce it can not live in the enviroment it is in, what happens to it.
>Particulate dust, with all nutrients removed?
>Bacteria waste from nitrate reduction?? and then same thing with the presence of ammonia?
>Biproduct enzymes used in denitrification??
>Sulfides? and in all other forms.
>methagenes?
> end products detritus. As in all othe products entering the bed that are not gassed off. Which is the vast majority of them.
I agree some will become surface area but what enviroment will they induce??

However, anaerobic bacteria would not survive in an environment in which too much oxygen is present, such as near the surface levels

If you are refering to anaerobic bacteria that perform denitrification, they will not only survive oxygenated zones they will proliferate. Denitrifing bacteria are faculative. if you are refer to SRB's (sulfer reducing bacteria) then yes they will not do well, BUT they have the ability to create and maintain anaerobic zones through complex biofilms. A big problem the navy has these days with keeping the boats from fouling.

All living populations will migrate given the correct conditions.

yes but keeping in concideration the size of a bacteria, the distance it would have to travel and it life span, I would say a small amunt would migrate and begin the culture in the other flask, but the vast majority would die first. The end result would be a population at equalibrium in both flasks, but IMHO not by migration.

Granted this could be risky if not done correctly and one waited until the bed was nearly saturated. However, by isolating the remote bed from the top tank, changing a fraction of the substrate very carefully, and then doing a complete water change in the remote tank, letting it sit for overnight with an air sparge, maybe doing another complete water change the next day and then sparging again overnight. I would bet my tank contents that the remote tank could be brought back online and re-connected even if the bed were nearly exhausted. However, I haven't never done it so...???

Agreed, I have done this a few times and it is the safest method.

You are exporting nutrient compounds contained in the bacteria and infauna as well as metals and toxins bound to the substrate along with much of their waste material. By providing an effective export mechanism for phosphate, and other problematical regime 3 compounds which are not effectively removed by water changes, this should theoretically stabilize phosphate concentrations in the system to some equilibrium level rather than allowing them to accumlate until the bed is saturated.

MY GOD Collin, that almost does the same thing as I do when I remove and skim out the detritus automatically with flow and skimming???


Mike

 

[mojoreef]

Ok if you dont agree that a remote bed is less effective then one in the tank, you have to explain. No free rides here, lol

Here I disagree. Contact time will have nothing to do with nutrient filtering capacity. Too much flow is bad for infauna and of course you don't want to blast things off the glass and such, but the filtering will remain effective for any soluble materials such as Nitrate etc. My system has about 400 gph going through it.

yes it wont have anything to do with the compacity, but it will have alot to do with the ammount of nutrients that are made available to them.

You should tell the theory above to the culerpa exploding out of my refugium and the swarms of pods and worms in there. Also, when I blow my detrius off the rocks and sand bed, the refugium gets plenty of debris.

Collin I am not saying that it wont work, I am just pointing out that it is not as effective as if it were in the tank. I have far better flow in my tank then anyone could ever have it they had a sand substraight, even with that I cant get it all out all of the time. So what ever doesnt make it out of the tank is part of the equation of ineffectiveness. What percentage do you figure you get out and to your remote??

take care


Mike

 

[mojoreef]

Oh one more. Particulate organic P, dissolved organic P and particulate organic P are not biologically available for higher plants such as calurpas (for the vast amount) so that leaves just dissolved inorganic P.

mike

 

[Craig Manoukian]

Great stuff Mike. I am slowly learning this stuff!

 

[cwcross]

Collin I do love talking with you.

Yes, I am enjoying the discussion also. However, you are making me learn too much biology!

Ok, lets look a little deeper. Simple stuff first.
>Chunk of food hits the bed and is brought down to the bottom of the bed through critter movement. In this area thier are no bacteria that can use it as it is not redued to a food source they can use. The bacteria that could reduce it can not live in the enviroment it is in, what happens to it.
>Particulate dust, with all nutrients removed?
>Bacteria waste from nitrate reduction?? and then same thing with the presence of ammonia?
>Biproduct enzymes used in denitrification??
>Sulfides? and in all other forms.
>methagenes?
> end products detritus. As in all othe products entering the bed that are not gassed off. Which is the vast majority of them.
I agree some will become surface area but what enviroment will they induce??

I don't think much unused food will make it to the bottom. I would imagine that what the crabs and shrimp and heterotropic aerobic bacteria don't get fast, that some sort of worm or heterotropic aneorobe will get. I doubt we would ever find a level of unused food in the sand bed. Even if it was unused and uneaten I would expect it still to act as a substrate.

If you are refering to anaerobic bacteria that perform denitrification, they will not only survive oxygenated zones they will proliferate. Denitrifing bacteria are faculative. if you are refer to SRB's (sulfer reducing bacteria) then yes they will not do well, BUT they have the ability to create and maintain anaerobic zones through complex biofilms. A big problem the navy has these days with keeping the boats from fouling.

Yes, to a certain extent. However, I don't know that they would thrive very well in competition with other more aerobics? In any case, the DSB will still become skewed and not work as effectively so I don't think it would matter.

yes but keeping in concideration the size of a bacteria, the distance it would have to travel and it life span, I would say a small amunt would migrate and begin the culture in the other flask, but the vast majority would die first. The end result would be a population at equalibrium in both flasks, but IMHO not by migration.

Agreed, I have done this a few times and it is the safest method.

Yes, this is what I mean by migration. This is a correct use of the term. Many people don't think of trees as migratory. However, we not have a migration of many sorts of trees towards the north. The trees don't crawl as we know, however, they die and new ones grow as the climate changes. It is the same with bacteria. Less competitive populations will die off and more competitive ones will grow faster until they are equal.

MY GOD Collin, that almost does the same thing as I do when I remove and skim out the detritus automatically with flow and skimming???


Mike

Ok Mike, I am sensing a bit of bias towards a BB setup. You may be right, they may be the best. I am not in a position to compare as I have never had one. However, I do BELIEVE that a refugium has much to offer an aquarium. As I stated before, it provides food for corals to thrive allows a higher bio-lode and allows a very maintenance free operation.

 

[cwcross]

Ok if you dont agree that a remote bed is less effective then one in the tank, you have to explain. No free rides here, lol

Somehow I knew you would say this

I don't think it matters very much how much detrius gets into the refugium. The main point here is to allow a place for plankton and macroalgea to grow. Also, as bacterial saturation in the main tank becomes near, nutrients will be released to the water and will become more available in the remote tank. At that point, bacterial migration will begin to occur so that the time until problems occur is extended. If substrate changes are done as we discussed then this process will equilibrate and we can maintain a position of no problems to extending the time until problems occur.

It is easy to talk about these processes as a step wise occurance. It is easy to conceptualize things in this way. However, in nature, things seldom occur like this. The system will maintain equilibrium at all times and so bacteria and nutrients will flow freely throughout the system. Yes, some will be sunk more quickly in the main tank and have a longer lifetime there, but infauna in the main tank bed, if there is one, or simply dissolution of nutrients from dying bacteria and processed food will exist in the water column and be carried to the remote. In the end, I would not expect there to be large differences in bacterial populations between the main tank and the remote. Especially if no substrate was in the main tank. What will happen is that as soon as Pi is released into the water it will be preferentially eaten by macroalgea or adsorbed onto the substrate before a bacteria can eat it. The rate of adsorption/desorption is millions of times faster that at which a bacteria can eat. So if you have substrate in the remote and none in the primary then as soon as Pi is released in any way, it will end up in the remote substrate to be eaten by bacteria there or will by used in macroalgea which can be exported.

yes it wont have anything to do with the compacity, but it will have alot to do with the ammount of nutrients that are made available to them.

Collin I am not saying that it wont work, I am just pointing out that it is not as effective as if it were in the tank. I have far better flow in my tank then anyone could ever have it they had a sand substraight, even with that I cant get it all out all of the time. So what ever doesnt make it out of the tank is part of the equation of ineffectiveness. What percentage do you figure you get out and to your remote??

take care


Mike

I get out maybe 10%. I only blow detrius about 2 times/month. My refugium is full of algea and critters. My small sand bed in the main tank is clean and clear, except for a little detrius and collects in a few spots, which I blow occasionally. All in all, I have little detrius in my tank compared to the amount of food I put in there. It is being stirred into the substrate in the main tank and exported via equilibrium to the remote. At some point soon, I will begin a schedule of small and partial substrate changes before my beds become saturated. I will test my theory on my own tank. In a few years I can let you know if it works maybe!

regards...Collin

 

[Scooterman]

Yep Great stuff, my tank is already looking better!

My latest purchase.

 

[Craig Manoukian]

Nice Scott!

 

[mojoreef]

I don't think much unused food will make it to the bottom. I would imagine that what the crabs and shrimp and heterotropic aerobic bacteria don't get fast, that some sort of worm or heterotropic aneorobe will get. I doubt we would ever find a level of unused food in the sand bed. Even if it was unused and uneaten I would expect it still to act as a substrate.

Collin this is a very important thing to the overall concept of a sediment system, basically a make it or break it type of thing. Food or waste that may travel deeper into the bed not fully reduced, will cause ammonia to be present through out. When that occurs the ammonia will prevent the bacteria from producing the first enzyme required in denitrifiation. When that occurs the whole nitrogen cycle, cycles and does not off gas and export.
Now for a moment transpose that into the wild. Reefs in the wild are subjected to high flow and wave action, this greatly stirs up the sand that may suround the reefs and blows the detritus out of the top few feet of it. Usually this detritus is taken to lagoonal areas or to the abysals (always associated with a reef. This lack of nutrient sinking is what allows for the nutrient free water conditions.

Yes, to a certain extent. However, I don't know that they would thrive very well in competition with other more aerobics? In any case, the DSB will still become skewed and not work as effectively so I don't think it would matter.

Through respiration Collin oxygen content will always be lowered rapidly and the enviroment will once again be skewed to accomidate the faculative bacteria. This is the game, and what will eventually be the down fall of the sediment system.

Ok Mike, I am sensing a bit of bias towards a BB setup.

No not really its more the concept of removing nutrients rather then composting them. For me anyway BB is the easist way of accomplishing that.

I do BELIEVE that a refugium has much to offer an aquarium. As I stated before, it provides food for corals to thrive allows a higher bio-lode and allows a very maintenance free operation

Ahhh now this is a whole other thread Collin, :razz: See I view a refugium as another bioload that lowers the ammount of bioload that could be taken up by critters I actually want to keep. I believe it produces very little food for the tank (for the bed yes) and the food souces it produces are inferior to what I can feed myself. I also dont like the lack of control of the amount of food a refugium adds to the overall system. But like I said we should make that another thread.


Mike

 

[mojoreef]

I don't think it matters very much how much detrius gets into the refugium. The main point here is to allow a place for plankton and macroalgea to grow.

Well if the detritus doesnt get into the refugium which is your filtration source then where does it stay or go, and what do you do to deal with it??
Macroalgae is a toxin producer, why folks use is is beyond me. The vast majority of plackton produce in a refgium, lives and dies in a refugium and to be honest is a low nutritional food source.

Also, as bacterial saturation in the main tank becomes near, nutrients will be released to the water and will become more available in the remote tank.

Thats seems to be a tough situation. So the concept is to wait for the main system to become saturated so that it feeds the remote system?? So do you figure nuisence algae is going to allow oll that nutrient laidened water to just pass by, or do you figure the main will begin to bloom?

If substrate changes are done as we discussed then this process will equilibrate and we can maintain a position of no problems to extending the time until problems occur.

Hmm that sounds like a chinese proverb :lol: J/K And all this is to be done instead of simply removing the detritus prior to reduction?? Let me give you a different look on the system you are discribing.
To me it is a house of cards, each part intigral and dependant on the previous. The concept is to build an enviroment (DSB) that is skewed to the popluation of bacteria that is dependant on an ever deminishing amount of larger critters (worms and such) to migrate nutrients through the bed to the bacteria. In a perfect sstuation the detritus would be cycled and off gassed as nitrogen gas, if everything goes right all the time. Beyond nitrogent based products the bed is totally ineffective and sinks or leaches the balance of products and biproducts back into the main system. All of this process in controled by biological populations (which you have no control over in thier constant state of flux) and chemical reactions which are also dependant of the flux occuring. Then we attach a remote sand sediment system to take up the slake for the main system and again introduce an huge bioload (the dsb itself) to the system, with all the known problems the first one has. But know we throw macro algae into the fray,which is an orginism that loves to proliferate and has the toxic ability to defend itself. Even taking into concideration that the cell structure of algae makes it leach out close to the amount of nutrients it absorbs we still get a net gain. So we harvest the algae allowing it to spore and possibly enter the main system (been thier) and in doing so release the toxins it uses as defence mechanisms to subject our corals and other critters to it. The enviroment that we create in the remote allows for the uncontrolled uncheck growth and death of critters (from pods to some form of planktonic life) with in its self. So we have a fairly poor nutritional value type of food in which very little leaves the remote that sits thier a flxes in life and death cycles, basically feeding itself. Also another hit on the overall bioload taking away from a more desired bioload such as maybe corals and/or fish.
Now if you run into trouble, such as say a power outage or a heater failure or and over heating or anything simular, you have a lot of biological dependance that is going to take a hit. Oxygen depervation, will kill anyone of these system, going sexual would be another huge hit, an event that disrupts or kills the critters that the sediment requires to be functional. The time limit runs out of what the sediment sytem can do or hold and the WHOLE house of cards come crashing down, and all of this is to create a simple more maintence free filtration system for the removal of detritus??

Just another way to look at it

Mike

 

[cwcross]

Ahhh now this is a whole other thread Collin, :razz: See I view a refugium as another bioload that lowers the ammount of bioload that could be taken up by critters I actually want to keep. I believe it produces very little food for the tank (for the bed yes) and the food souces it produces are inferior to what I can feed myself. I also dont like the lack of control of the amount of food a refugium adds to the overall system. But like I said we should make that another thread.


Mike

Yes, I agree. A topic for another thread. I think we accomplished the goals here. To summarize:

I think we all agree that a DSB can be prone to problems after some time.

Whether the DSB has benefits that outweigh the problems is an individual choice.

In any case, it is possible to help prevent or prolong these problems from occuring by doing substrate changes, although one should be very careful while doing so.

Some believe that a BB system is superior for helping to prevent these problems.

I don't see that we have much to gain from further discussions. Interesting and worthwhile topic and I learned much.

Regards...Collin

 

[cwcross]

Mike,

as regards to your last post. You make the refugium sound like an avalanche or something. Mine seems to be working quite well and I can see it spit out pod oriented food about once every 20-40 minutes. My tang and clarki race to eat it. Sometimes the chromis beat them to it. My Corals do very nicely with no supplementation. It seems to be providing a nice benefit. I don't have to feed but about every day to every other day very lightly. Anyway, that is another topic..

best regards...Collin

 

[Craig Manoukian]

Macroalgae is a toxin producer, why folks use is is beyond me.

So what is macroalgea's benefit in nature if it is so bad in a closed system? TIA Mike!

 

[mojoreef]

Interesting and worthwhile topic and I learned much

Agreed, so have I. and I agree with you sumerizing.

as regards to your last post. You make the refugium sound like an avalanche or something.

ROFL yea I guess I was a tad harsh on it, I was more or less try to show that because something is a natural system it does not mean that it is a simple system. In reality natural system are very complex and the variables are mind blowing. When I person puts together a system of natural filtration and food production such as the one I discribed, they have created a very complex and interdependant system. I dont mind what so ever if that is what they wish to do, I just want to make sure they understand what is happening and what the pros and cons are, thats all.

Lets start up a refugium thread say in the advance topics and have another good conversation.

take care and thanks for a very knowledgeable thread.


Mike

 

[mojoreef]

So what is macroalgea's benefit in nature if it is so bad in a closed system? TIA Mike!

Well macro algae is the first sign of a reef in decline. In a wild reef that is healthy the enviroment can not sustain the nutrients required for macros to proliferate. Once the reef eurthrophic (nutrient laidened) macros begin to dominate and thus the reef is on the way out.
Look at it like this Craig. You have a plate of food that is left over from dinner, do you toss it into the lawn in order to have the grass take up the nutrients with in it, and to promote the worms and other things below the grass to grow and reduce it. Thinking that by cutting the grass you are now getting rid of the problem. Or do you take it to the curb and call it a day


Mike

 

[Craig Manoukian]

Compost, compost, compost! All those grass clippings are turned back into the garden.

Was unaware that caulerpas were a sign of a reef in a state of decline, thanks as always. Is that the beginning of a down turn and then a rebirth of the reef or does the reef move itself? What causes the reef to become eurthrophic and is that what we model in our closed systems?

 

[mojoreef]

Is that the beginning of a down turn and then a rebirth of the reef or does the reef move itself? What causes the reef to become eurthrophic and is that what we model in our closed systems?

Sometimes the reef makes a come back if the enviroment becomes skewed more for thier liking, but not often. Lots of things can cause the situation, climatic change causes die of and the chain begins, runoff from land is a biggie, Nutrient laidened water coming from rivers and creeks, lots of things really. The concept of keeping a reef is usually to recreate the enviroment that the corals we are trying to keep come from. Ie: I perfer to keep corals that come from a very nutrient free waters, thus I do my best to recreate it with high flow, and the best exporting I can provide. A person that may want to keep soft corals or lagoonal corals may be better off running a Sand sediment system, that will provide the nutrients and massive food sources that they need. So the over all concept is to try to recreate a system that best resembles the envroment that the critters they are keeping comes from. that make and sence??


Mike

 

[cwcross]

This may be true in nature. However, in the aquarium I think the macro's can play a different role. In an aquarium, you are going to have excess nutrients. There is no way to avoid it. Be keeping Macro's in the refugium and letting them get established, they will compete with algea in the main tank and outcompete them.

I think of it like this. I add top off water that contains phosphates and silicates. This is going to fuel the growth of algea. Since there is much algea in the refugium, this algea will use the nutrients and grow before algea in the main tank can use it. They will therefore soak up all the excess nutrients and lower the concentration in the main tank. This helps to keep the water in the main tank more devoid of nutrients so the corals are happier.

I think this is reasonable...C