DSB tank crashing

[jeepboy]

Since some people experience tank crashes with a DSB, I am curious about how rapidly the crash occurs. Are there signs a crash will happen or does a crash happen overnight?
I have a DSB and think I have all the correct critters. If there are signs of a pending crash I would like to know so I can take the correct actions.

 

[footbag]

I belive that a blackening sand bed is a sign of impending doom. I feel that a crashing DSB is more of a result of improper fauna instead of a imminent timebomb.
DSB's are a hotly debated topic on other boards, but there is more support for them on this board.

 

[footbag]

Large black spots of sand that you can see through the glass. If you disturb them they stink and you get a PO4 spike. I belive that they are pockets of nutrients that are slowly processing.
If they process nutrients slower then they are added, then that would set the stage for a crash.

 

[footbag]

how do i get rid of the black spots??
A diverse fauna will be the best way to prevent the black spots. Bristle worms, pods, crabs, conchs, etc...

 

[footbag]

There is an ongoing post in another forum about this specific issue. It is very interesting and scared the hell out of me. It has hundreds of follow ups, BUT nearly all of the posters are against DSB's. Like I said, hottly debated. I'll bump it for all.

 

[falconred]

this why we stay away ftom the deep beds . it is fact that nothing of any good lives below 2" of substright

 

[footbag]

nothing of any good lives below 2" of substright
How about the De-nitrifying bacteria? That begins at 4" below the surface, and is the reason that most people add a DSB.

 

[falconred]

ok bare bottom tanks there cleaner and for the most part have better water. deep sand beds are dirty. over time build up and nothing you can do for it 2" max

 

[footbag]

Bare Bottom tanks are cleaner meaning what?
As far as the build up, that is the debate. I have seen lots of DSB tanks that are just as succesful as a BB. Personally, I like the look of sand over a bare bottom, and my sand isn't dirty. Adding fauna is what you can do for it.
A good ? to debate would be...
Does a DSB present an imminent crash or are there steps one can take to prevent the crash?

 

[krustytheclownfish]

There is an interesting article in this years "Marine Fish and Reef" magazine about sand beds. In short, it says that 1 or 2 inches is all that's necessary for all the good stuff to happen...including denitrification. It doesn't say that DSBs are bad, just unnecessary. Is it right? I have no idea. :thinking:
Let's see...first bare bottoms, then crushed coral, then plenums, then DSBs, now just a little bit of aragonite...what's next? Kitty litter?
John

 

[falconred]

Does a DSB present an imminent crash or are there steps one can take to prevent the crash? i do not think you can stop it. like a sponge a small mess cleans up quick and easy as a reef gets older the mess gets bigger a sponge will no longer do the job .this is why we only use a max or 2" stars, crabs, snails ,fish will keep a good turn over in the SS nothing of any good lives below 2" of substright. this mess has no place to go but down soon build up .then the load for De-nitrifying bacteria is to big crash

 

[ekclark]

wouldn't the presence of a protein skimmer take away much of the risks associated with dsb's? People keep knocking these for different reasons, though I have never heard compelling evidence. If you are against dsb's, then do you also throw away your lr over a certain age, say five years? I am not trying to be a wise ---, I am actually asking these questions.

 

[dburr]

If you are against dsb's, then do you also throw away your lr over a certain age, say five years? I am not trying to be a wise ---, I am actually asking these questions
This is a great point. Some people do throw it away and start over. It is believed to get clogged like "the sponge" idea.
A DSB tank is NOT "dirty". It is just another way to filter the water.
My LFS owner has a tank at his home. It's a 500 gallon tank. Very deep tank. I don't remember how deep, but he can't reach the bottom, so, he put in a 8" DSB. He had it for 15 years. It crashed (the tank) because "meds" fell out of his pocket while cleaning the tank.

But, thats another story.

 

[jeepboy]

Beyond the debate of DSB's being good or bad, are there any signs that signal a DSB that is going to crash?

 

[beth]

I think any and everybody who even has a guppy tank has heard about the DSB hoopla at "the other site". So mentioning it here or not, we all know who what where we're talking about. More to the point is, that the person who is now anti-DSB used to be the same person who got us all using DSBs! LOL Time will tell. Personally, though, I am really enjoying my DSB at the moment at least and I"m rooting for it to be kicking for a long time.

 

[benj2112]

Originally posted by Magic_Carp
so if i add some nassarius snails he black "spots" should go away??
They would help with shifting the top layers of the sand, but I don't think they would make much of an impact on the "black". I think the fauna you need is more in the lines of the detritivore kits you can find in some places.
I think you have to figure out if the black is just alge/cyano or the "bad" stuff. I used to have a bit of black under the sand until I went to only feeding every other day, got some macro, and started using Rowaphos. Now nothing but a tiny bit of neon green algae in one spot. The other stuff has just gone away slowly over time.
Thats my 2 cents, anyway. I hope I am not too far off.

 

[jlem]

Originally posted by Beth
that the person who is now anti-DSB used to be the same person who got us all using DSBs! LOL
DR. Ron does like to change his mind
The reasons why I do not go with a DSB is because I don't really like the look of 4-6 inches of sand in my tank. I would much rather have more water volume and more swimming room for my fish. My bioload is also pretty light so a DSB would basically be useless in my system and just sit there taking up space in my reef.

 

[reverai]

Generally it takes years for a DSB to truly crash. And from reading , some DSB never have crashed after many years. Personanly I don't think a DSB is really needed to be a good thing any more. A sand bed of an inch or two seems to work just as well. It took a few years of research to figure this out so you find lots of people on both sides of this issue and to some extent both sides are right.
Steve

 

[jeepboy]

I set my 75g up with a DSB after learning about them here. The next tank I setup was a 55g and I read more about DSB alternatives and decided to try a SSB. Since both tanks are so drastically different I will probably not learn much about which one works better. I do know this, my LMB loves to messup my DSB all the time, which tends to deposit a lot of sand on the rocks.
I have some dark spots in my DSB that I can see on the side, and one time I did disturbe the DSB to move a large rock. That caused a horrific smell. I probably overfeed badly, although I don't think my fish would agree, they always want to eat.

 

[nm reef]

There are numerous methods/means of filtration available and using a DSB is just one of them. I have read volumes in the past year on why DSB's are destined to crash...and I've read just as much info on why they can be effective additions to the overall filtration. Lots of info but not a lot of hard facts. I use a 5" DSB in my display that has a rather large diversity of micro infauna with no current problems. I've also decided to run a 6"-7" DSB in my 55 gal refugium. IF problems develop in either it would be possible to remove both. Over time if a problem begins to develop I would probably go with a shallow sand bed in the display( I prefer the sandy bottom look) and continue to use a DSB remote in the refugium. My thinking is the DSB in the refugium could easily be isolated from the display and removed/replaced every few years if needed.:thinking:
I don't consider myself either experienced or a expert on the subject by any means...but I do know that neither of my sand beds have turned toxic and I have been pleased with the performance of the DSB's. They provide additional filtration properties...allow for diversity in micro infauna...and in my opinion provide a more natural appearence.