Dsb's work, what makes them work best?
- Thread starter barryhc
- Start date
I agree. I haven't yet bought a PO4 test kit because I'm just not sure how useful it will be. My current leanings/thoughts on PO4 and growing stony corals are that the best solution is to just go BB and make sure that the water is kept so nutrient poor via high flow and wet skimming that macro won't grow at all. That way one would know that there is no phosphate problem.
But what I would really, really like is for some of the DSB folks to propose a mechanism for how a DSB deals with PO4. It just seems to me that every time the topic comes up and the questions are asked, there's never a real answer of what is going on in there. There are, however, some proposed mechanisms for how DSB's can fail due to phosphate accumulation that seem to make sense. At least to me.
That's a bit discouraging in that I firmly believe that, based on the prescribed methods posted here on RC, I could make a BB tank work. And at this point I think it would probably be cheaper, require less mainenance, and probably grow stony corals faster than using a DSB. And yet I want sand in my tank. I like the way it looks. I'd like to keep critters that like sand. And we can see that some folks make them work acceptably well for years. But I have yet to see anyone describe a clear and straightforward approach that makes me feel confident that I'd be one of those who make them work for years. So at this point I'm anticipating the possibility that, like Joe, I will have to remove it at some point in the future. And that doesn't give me a warm fuzzy feeling. So for now, I keep following threads like this and hoping.
joefish
Premium Member
.<a href=showthread.php?s=&postid=6501817#post6501817 target=_blank>Originally posted</a> by aubee91
I would have expected you to see algae on the DSB as well. Were you getting measurable levels of PO4 in the water column?
No , not any..
Another thought or speculation...is it possible that you had an adequate amount of critters to keep the bed clean so it stayed white, I agree here. but that it had still sunk enough phosphate that it was leaking? but not here.
quote:
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Originally posted by inwall75
All I can say is, "Boy am I doing EVERYTHING wrong". I use sediment sizes that critters "can't" live in on occasion. I siphon solids out my sandbeds on occasion to make my beds last longer.
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How can it be, that Inwall75, can use sediment sizes that critters "can't live in" ( without a grain size specification ), and you respond that there is nothing wrong with that, BUT with the specific grain sze of .5 to 1.5mm ( which averages 1.0mm ), you state that the sand bed will "be killed" ? ? ?
Are you suggesting that the tank can be run with a "dead sand bed" and still be successful?
If so, then maybe this is the answer. How do we run these successful tanks that operate with a dead sand bed?
I might want to use this method.
> barryhc
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Originally posted by inwall75
All I can say is, "Boy am I doing EVERYTHING wrong". I use sediment sizes that critters "can't" live in on occasion. I siphon solids out my sandbeds on occasion to make my beds last longer.
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How can it be, that Inwall75, can use sediment sizes that critters "can't live in" ( without a grain size specification ), and you respond that there is nothing wrong with that, BUT with the specific grain sze of .5 to 1.5mm ( which averages 1.0mm ), you state that the sand bed will "be killed" ? ? ?
Are you suggesting that the tank can be run with a "dead sand bed" and still be successful?
If so, then maybe this is the answer. How do we run these successful tanks that operate with a dead sand bed?
I might want to use this method.
> barryhc
While the rocks sitting in the gravel is not a particularly good thing, over the "very long run", I don't see that as a problem "early on" like you were, when the the problem was occuring.
I had the very same reefer rocks that you had, and finished curing them in the tank, although I did not do any "dunking and swishing, and as you noticed, my PO4 levels took a lot longer to drop.
The only other really different thing is that I had that "over abundance" of crabs and snails, most of which I still have today.
I think the crabs and snails have kept the algae at bay, and it may be that if "they" trim down the algae very fast right from the beginning, that the macro algae just never gets a chance, from the time that it is tiny. I also wonder if the crabs and/or snails, "might mow" down the Macro, while it is tiny, along with everything else, and then won't eat it after it has become larger, if it has been allowed to fo so, by way of not enough dertivores, from the "get-go".
I had a cyano outbreak in the little walmart refugium, shortly after I set it up, and after a couple of weeks I decided to transfer some of the snails and crabs into the refugium.
It took about 3 weeks, and all the algae was gone in the refugium as well. Other than a bit of culerpa in the refugium, that grows very slowly, and some chaeto that just about won't grow, I still have no algae and no cyano anywhere in either tank, for the last 5 mos. now. I don't do any maintanence at all.
My Nitrate is a bit high, and my PO4 is much too high, at .1 to .4ppm. I have far too much "predation" in the tank, in the form of crabs especially, and possibly starfish, peppermint shrimp, and cucumber.
The bed's "fauna" is rather sparse as a result, and I have to make an adjustment here eventually.
All of the animals are very happy, with the exception of some SPS frags, and they are suffering firstly from rather poor light, and likely the PO4 level as well. Calcification has not been a problem, but white band disease ( or something similar ) has been, with brown algae following on the skeletons, weeks later.
My point here is that the crabs and other scavenger-carniores have kept the bed and the rocks clean, and then left me with an overly "predated" sand bed. Therefore this is only an interesting observation, and not a reccomendation of any sort.
Still, my rocks are the cleanest you will ever see, that have not been cooked.
Algae does not build-up on the 4 panes of glass that I cannot scrape, or any of the equipment either, except a spot the size of a quarter where a rock touches the glass.
To finish up Joe, there are a few "macro algaes" that the critters just won't eat, and at PO4 levels that are quite acceptable even to SPS, these certain algaes can continue to grow, if predation does not keep them pruned.
I had only one such specie', which survived all the crabs, and I physiclly removed it from the display, and put it into the refugium.
That one example has maintained itself free-floating in the refugium at the size of a golf ball. Anything else in the display either died, or is too small to see ( even with a magnifying glass ), as a result of the still rather high crab and snail population.
> barryhc
alten78
New member
<a href=showthread.php?s=&postid=6501918#post6501918 target=_blank>Originally posted</a> by aubee91
I agree. I haven't yet bought a PO4 test kit because I'm just not sure how useful it will be. My current leanings/thoughts on PO4 and growing stony corals are that the best solution is to just go BB and make sure that the water is kept so nutrient poor via high flow and wet skimming that macro won't grow at all. That way one would know that there is no phosphate problem.
This seems to be one of the common denominators for all dsb v. bb threads that always go south, for the sake of everyone that has made this thread an enjoyable learning experience, lets not debate on this
But what I would really, really like is for some of the DSB folks to propose a mechanism for how a DSB deals with PO4. It just seems to me that every time the topic comes up and the questions are asked, there's never a real answer of what is going on in there. There are, however, some proposed mechanisms for how DSB's can fail due to phosphate accumulation that seem to make sense. At least to me.
I believe this has been discussed over a majority of the thread and im not sure if there is a clear "real" answer, at least one that I cannot begin to sum up briefly.
ALRIGHTY THEN ! ! ! ! ! !
Thanks to Alten and Aubee both , and everyone alse as well of course ! ! !
I have been holding back for quite a while on this, since we need to understand "existing" sand bed concepts, before we start experimenting, or utilizing "unconventional" concepts to operate our "CAPTIVE REEF AQUARIA", but it now appears as if we need to look "into the future", or "at alternative concepts", in order to find a solution, or solutions to the potential limitations of the "Charachteristic" Deep Sand Bed.
This is certainly not a condemnation of DSB, on the contrary, it is in the interest of further promoting the concept, for many DSB users, and even some BB users, that wish they could have sand ( or other substrate ) as well, that I will now bring up some "Alternatives", or Modifications" to the "Classic" Deep Sand Bed.
There are at least three alternatives( or variations ) to the Classic DSB, and I will list those three here:
1 > RUGF "Reverse Under Gravel Filter"
Now it has been stated, 20 or 30 years ago that this cannot work, because of "Nitrate production", just like "Classic Bio-Balls".
It just isn't so, but since it was originally applied to a "straight grade" of Dolomite, at usually about 3 to 5 mm grains and only 2 to 3" depth, and with too much flow "to boot", it usually did just that .
Usually I said, but not necessarily, just ask "PaulB". He will show up here eventually, and keep the truth "rolling", I'm quite sure.
2 > Then there is my "favorite", Wasting Plenums". Those got tried before, and "didn't work", right ? That isn't really accurate, but we'll beat around on it some I'm sure.
3 > "Rubble Bottom", in some cases, this can be very similar to BB, if that is your preference, but that doesn't have to be the case. Actually there are versions that incorporate various substrates, in conjunction with the "Rubble", and it is an interesting and potentially valuable option.
Then there can, or "could be" various combinations of the above that could be used to create "Zones" within usually "larger" aquaria, for a "Maximized" Bio-Diversity. this is my "true favorite".
I have investigated these options at length, and I can tell you now, that there isn't a "little book" that explains how to do any of
them.
There isn't a "Big Book" either, but The "Biggest Book of all" is the "Forums" and here we are, now aren't we?
At this point, I think we need to admit, first off, that we cannot duplicate the ocean within our "little tanks", even if they are "a thousand gallons". It just IS NOT GOING TO HAPPEN.
What we need to accomplish is a result that is "close enough" to handle the animals that we "want to keep". This will vary from one aquarium to another.
This just does not include BB as an option, because, by "definition", it applies when the aquarist "WANTS TO HAVE SAND OR OTHER SUBSTRATE IN HIS OR HER TANK", for whatever reason.
Every kind of "Bell and/or Whistle" can be included, but not limited to, skimming, refugium, this reactor, that reactor, UV, Carbon, etc. etc.
There is not a good reason to get into "exclusivity of systems" within this discussion.
Without any further A-D-O-O, discuss whatever you please that relates to sand beds.
Happy Reef Keeping ! ! ! > barryhc
Thanks to Alten and Aubee both , and everyone alse as well of course ! ! !
I have been holding back for quite a while on this, since we need to understand "existing" sand bed concepts, before we start experimenting, or utilizing "unconventional" concepts to operate our "CAPTIVE REEF AQUARIA", but it now appears as if we need to look "into the future", or "at alternative concepts", in order to find a solution, or solutions to the potential limitations of the "Charachteristic" Deep Sand Bed.
This is certainly not a condemnation of DSB, on the contrary, it is in the interest of further promoting the concept, for many DSB users, and even some BB users, that wish they could have sand ( or other substrate ) as well, that I will now bring up some "Alternatives", or Modifications" to the "Classic" Deep Sand Bed.
There are at least three alternatives( or variations ) to the Classic DSB, and I will list those three here:
1 > RUGF "Reverse Under Gravel Filter"
Now it has been stated, 20 or 30 years ago that this cannot work, because of "Nitrate production", just like "Classic Bio-Balls".
It just isn't so, but since it was originally applied to a "straight grade" of Dolomite, at usually about 3 to 5 mm grains and only 2 to 3" depth, and with too much flow "to boot", it usually did just that .
Usually I said, but not necessarily, just ask "PaulB". He will show up here eventually, and keep the truth "rolling", I'm quite sure.
2 > Then there is my "favorite", Wasting Plenums". Those got tried before, and "didn't work", right ? That isn't really accurate, but we'll beat around on it some I'm sure.
3 > "Rubble Bottom", in some cases, this can be very similar to BB, if that is your preference, but that doesn't have to be the case. Actually there are versions that incorporate various substrates, in conjunction with the "Rubble", and it is an interesting and potentially valuable option.
Then there can, or "could be" various combinations of the above that could be used to create "Zones" within usually "larger" aquaria, for a "Maximized" Bio-Diversity. this is my "true favorite".
I have investigated these options at length, and I can tell you now, that there isn't a "little book" that explains how to do any of
them.
There isn't a "Big Book" either, but The "Biggest Book of all" is the "Forums" and here we are, now aren't we?
At this point, I think we need to admit, first off, that we cannot duplicate the ocean within our "little tanks", even if they are "a thousand gallons". It just IS NOT GOING TO HAPPEN.
What we need to accomplish is a result that is "close enough" to handle the animals that we "want to keep". This will vary from one aquarium to another.
This just does not include BB as an option, because, by "definition", it applies when the aquarist "WANTS TO HAVE SAND OR OTHER SUBSTRATE IN HIS OR HER TANK", for whatever reason.
Every kind of "Bell and/or Whistle" can be included, but not limited to, skimming, refugium, this reactor, that reactor, UV, Carbon, etc. etc.
There is not a good reason to get into "exclusivity of systems" within this discussion.
Without any further A-D-O-O, discuss whatever you please that relates to sand beds.
Happy Reef Keeping ! ! ! > barryhc
You could have modified the flow level, thickness of the substrate, or the size of the grains IMO to solve a lot of this problem.
I was PM'ing John Laurenson (Ldrhawke) on another board recently and he confirmed that this method does in fact work. For those who've not heard of this, here's the thread that first AFAIK discussed this. http://www.reefcentral.com/forums/showthread.php?s=&threadid=289910&perpage=25&pagenumber=1
If this interests you, there's a great thread started by Barry here. Plenums and the Wasting option
When I had a DSB in my 75, this would probably be what I had. I had a very fine sand that I couldn't get to stay on the bottom of the tank. Then I mixed in sand mixed with a much larger size grain that everyone said shouldn't be in a sandbed. Over time, the mixing that I did mostly undid itself. The larger grains defied gravity and rose to the top (or more accurately, the smaller grains sank). The cool side-effect was that I've typically had more flow than most of my friends were able to achieve in their DSB tanks. I think this additional flow was extremely useful in my DSB.
Paul B
Premium Member
I have something to say about the Reverse undergravel filter mentioned by barryhc. I think it's safe to say that I have the longest running RUGF here, (probably the only one)
UG filters were the backbone of this hobby for many years in fresh water and salt. They were advocated for saltwater by
Robert Straughn in the fiftees. (Salt Water Fish Keeping in The Home) He was considered "The Father of saltwater fish keeping for good reason. He was a renouned collecter, breeder and author long before any of the people who are now considered experts. You don't know him because unfortunately he died.
Anyway, the man kept just about anything you can imagine and he just about invented UG filters.
The problem was that there was no reef tanks then and nitrates were not a problem, they were not even mentioned until about the seventees. UG filters work great except for a big problem. When used in a reef, they are too good at what they do just like bioballs. The concept to use the entire bottom of the tank as a filtration method is sound but in a reef we have to modify the way it is used. Our strategies have been modified in this hobby since it started in about 1970 and the UG filter must be modified as well.
To control nitrates it should be run backwards, or in reverse. There is no magic in this, the bacteria do not care one way or another, we run it in reverse so we can strain the water going through it, we just want water under there, no detritus. So a filter, sponge, strainer etc is needed on the intake of the powerhead. Also, it should be run very slow, I use 50 gph down each tube. That is slow, I use a manifold where the three tubes are connected together and I pump 150 gph in it. It is run slow because I want anerobic areas to develop in most of the spots where the gravel surfaces are touching each other but not having large enough places to develop hydrogen sulfide.
I removed my UG filter plates almost two years ago to see what was under there, The last time I did that was 25 years prior.
There was detritus under there but not that much, most of the gravel was full of tube worms.
Does it work? I think so and there is very little maintenance except that 25 year cleaning and I stir up where I can reach about twice a year and suck it out with a diatom filter.
My nitrates are zero and the tank will be 35 years old next month.
Have a great day.
Paul
UG filters were the backbone of this hobby for many years in fresh water and salt. They were advocated for saltwater by
Robert Straughn in the fiftees. (Salt Water Fish Keeping in The Home) He was considered "The Father of saltwater fish keeping for good reason. He was a renouned collecter, breeder and author long before any of the people who are now considered experts. You don't know him because unfortunately he died.
Anyway, the man kept just about anything you can imagine and he just about invented UG filters.
The problem was that there was no reef tanks then and nitrates were not a problem, they were not even mentioned until about the seventees. UG filters work great except for a big problem. When used in a reef, they are too good at what they do just like bioballs. The concept to use the entire bottom of the tank as a filtration method is sound but in a reef we have to modify the way it is used. Our strategies have been modified in this hobby since it started in about 1970 and the UG filter must be modified as well.
To control nitrates it should be run backwards, or in reverse. There is no magic in this, the bacteria do not care one way or another, we run it in reverse so we can strain the water going through it, we just want water under there, no detritus. So a filter, sponge, strainer etc is needed on the intake of the powerhead. Also, it should be run very slow, I use 50 gph down each tube. That is slow, I use a manifold where the three tubes are connected together and I pump 150 gph in it. It is run slow because I want anerobic areas to develop in most of the spots where the gravel surfaces are touching each other but not having large enough places to develop hydrogen sulfide.
I removed my UG filter plates almost two years ago to see what was under there, The last time I did that was 25 years prior.
There was detritus under there but not that much, most of the gravel was full of tube worms.
Does it work? I think so and there is very little maintenance except that 25 year cleaning and I stir up where I can reach about twice a year and suck it out with a diatom filter.
My nitrates are zero and the tank will be 35 years old next month.
Have a great day.
Paul
CaptainCoral
New member
That's Awsome Paul!
I've been curious about your RUGF set up for some time now. I'm glad you chimed in here, and gave us all some details.
I've been curious about your RUGF set up for some time now. I'm glad you chimed in here, and gave us all some details.
