DSBs & long term viability, the evidence against..

[Achilles Tang]

The recent year had more & more evidence coming out against the long-term viability of the DSB.

The about-face turn by a major authority & proponent of the DSB in the USA is also deeply disturbing.

It's still a fantastic natural nitrate-reducing method and provider of natural zooplankton but recent evidence shows that it does contribute to 'old tank syndrome'.

It seems like a big enemy of the reef tank, phosphate, will leach out over time...

a major consequence of the DSB being a nutrient sink, causing unexplained algae blooms and corals becoming unhealthy.

A recent study of my DSB has also yielded evidence that it has become rather devoid of microlife, a crucial factor in the effectiveness of a DSB. Without sandbed critter recharge kits with enough diversity, are our sandbeds becoming virtual deserts, a nutrient cesspool and a ticking timebomb?

The trend now is that some very experienced SPS keepers are moving away from a sandbed and relying on just turbulent water circulation to keep detritus afloat, coupled with a very good skimmer and believing that if you prevent detritus from building up & export it fast enough, you can effectively control nitrates & phosphate.

In their opinion, using starboard bottoms, although fake looking, is the alternative to a bare bottom tank. It will become natural looking over time with coralline algae (a little weird to have a pink-bottomed tank, IMO).

With better and better water circulation devices coming up eg. Tunze wavebox, achieving the lifting of detritus, will this be the new trend in SPS reefing?

Let's discuss the evidence. Keep it serious, folks!

[RAV-65]

Without the use of DSB, wat other methods do we have besides using a refugium??

I've tried using a refugium before, but I find it troublesome due to the constant pruning required and also it's a big mess in the sump... Reefing would be best, when minimal maintainence is required, yet I find myself struggling with my tank on a daily basis! When can I sit back, relax and just watch my tank?

Wat about plenum?? heard alot of good reviews, but not many reefers using plenum so hardly any feedback here...

Help!!!

[AlfaRomeo]

In my relatively short time in reefing, I have also noticed a shift in mentality at RC.

Logically, if the water movement in the tank is high enough with a lot of turnover into the sump and the skimmer is efficient enuff to remove all DOCs before they break down , there will be no need for the DSB to add as a NNR. Sufficient LRs would also aid in NNR.

To add another angle to the discussion, ZEOvit which aims to replicate the low nutrient environment in Fiji etc etc have also indicated that a DSB will be a detriment to the process due to the stored nutrients which will seep back into the water column.

Maybe a compromise of a SSB would give a more natural look to the tank without the fake look of the starboard.

[Ancelot]

I still need to stress the must when everyone employs DSB is the need of a GOOD skimmer! Phosphate leech, algae blooms are all because of bad and inefficient skimming. Even if you have beckett, you cant control phosphate but can minimise as WL has said, but ill maintained beckett will eventually failed to a well maintained air driven skimmer in times to come if you are lazy. Reefer_guy has healthy sps because of his diligience not because of miracles. Miracles does not come from the skies it comes from hardwork. If we are diligent, i believe we can run away from the old tank syndrome. I have seen typical cases of good tanks and good-to-bad tanks and really bad tanks. And it all still boils down to diligence.

DSB lacks of live? hmm.. are you talking about amphipods, cpoepods or other critters? imo, i think as a practice we should change our live rocks once a year. There are some american reefers who have taken to the extremes. Instead of buying, they seed their own rocks by growing a healthy population of copepods and algae (bear in mind its not caulerpa i am talking abt) and when their main tank's live rocks run out of live, they change and transfer. though bad to the corals, but definitely beneficial to the sand bed. but if we are doing changes on those smaller rocks i dont see why not? can always try eh?

Just my 2 cents worth..

[Jun Hong]

I think the problem of having DSB in show tank is there are so many predators that may eventually threaten the long term survival of sandbed critter.

That why I set up a remote 2ft refugium tank with DSB for my 2ft main tank. If the DSB start contributing the 'old tank syndrome' after long run, it is still easy to restart the DSB without disturbing the main tank.

But it is still crucial to have the remote DSB surface area large enough for the main tank.

[Ancelot]

I still support DSB afterall, it is the closest system to nature. Though more maintence needed, but if I can see my hardwork paid off, I find greater satisfaction tin viewing my healthy LS than watching tv or playing games. And yeah! i agree with AT, it looks weird to have a bare bottom tank. Even encrusted with coralline, yucks.. it still feels weird.

Refugeim? Hmm.. i never tried this method before because i find it a waste and not really an effective nutrient export. and the way we employ the refugeim i think is wrong. the design is wrong. We should have a valve at the bottom of the refugeim to drain away the detrius and not a sand bed to collect them. Having a sand bed is not wrong but more maintence in gravel washing is required right? Dont believe, tonight go take a look at your refugeim see how dirty is it and how thick your detrius you have and you will believe what i say. And a refugeim is no diff from a DSB if we dont maintain it.. they will become time bombs eventually!

I believe in DSB. I trust my skimmer my main tank and of course my carbon. and additional water changes, So dsb i believe is the closest we can get to nature unless someone comes up with something much better than dsb.

Just my 2 cents worth..

[Jun Hong]

Dont believe, tonight go take a look at your refugeim see how dirty is it and how thick your detrius you have and you will believe what i say. And a refugeim is no diff from a DSB if we dont maintain it.. they will become time bombs eventually!

Isn't it serve the purpose that high flow in main tank keep the detrius suspended and eventually those detrius end up in low flow refugium and let the cleaning crew do their job.

[Ancelot]

Jun Hong dude, do you have like fishes in your remote tank? If have, thats good your method is working. If not, add a one or two damsels to have a nitrogen cycle and upkeep the live in the rocks as well as in the sand.

My 2 cents worth..

[XPeriment 626]

Jun Hong dude, do you have like fishes in your remote tank? If have, thats good your method is working. If not, add a one or two damsels to have a nitrogen cycle and upkeep the live in the rocks as well as in the sand.

My 2 cents worth..

Is there a need for this? Shouldn't the waste from the main tank be sufficient to maintain the bacteria in the remote tank? Seems like a redundant act to put fish in the remote tank.

[Jun Hong]

Isn't it serve the purpose that high flow in main tank keep the detrius suspended and eventually those detrius end up in low flow refugium and let the cleaning crew do their job.

No predator (including fish) in the remote tank since it serve as a refugium tank with DSB.

[XPeriment 626]

Jun Hong dude, do you have like fishes in your remote tank? If have, thats good your method is working. If not, add a one or two damsels to have a nitrogen cycle and upkeep the live in the rocks as well as in the sand.

My 2 cents worth.. 

Pardon my ignorance but what's the difference between a remote tank and having a DSB in your sump?

[Ancelot]

hahaha.. i dont really trust my lazy bum cleaning crews that much. They may be wild caught but inside a tank where food just drop from the skies they become lazy eventually. tats a natural habit. so i still want to be the sole person to clean up the tank. But how many people are so hardworking still after a day's work to clean up a smelly refugeim? I dont admit tat i am hardworking on my tank. tats why i choose to drop the refugeim, until i have come up with a better design to manage the refugeim. Right now, i can only do gravel washing weekly...

Just my 2 cents worth..

[Jun Hong]

Pardon my ignorance but what's the difference between a remote tank and having a DSB in your sump?

Is the same provided the surface area of the DSB is large enough

But I believe it is quite difficult for those reefer to have a 4ft main tank and 4ft remote DSB tank

For me, I have 2X1.5X1.5 main tank and 2X1.5X1.5 remote DSB tank.

[Ancelot]

OOPs.. sorry.. i think i get your picture le.. i tot you had a separate tank.

Sorry!

[weileong]

I still need to stress the must when everyone employs DSB is the need of a GOOD skimmer! Phosphate leech, algae blooms are all because of bad and inefficient skimming. Even if you have beckett, you cant control phosphate but can minimise as WL has said, but ill maintained beckett will eventually failed to a well maintained air driven skimmer in times to come if you are lazy. Reefer_guy has healthy sps because of his diligience not because of miracles. Miracles does not come from the skies it comes from hardwork. If we are diligent, i believe we can run away from the old tank syndrome. I have seen typical cases of good tanks and good-to-bad tanks and really bad tanks. And it all still boils down to diligence.

You talking about old tank syndrome? Like using kalkwasser to solve PO4 problem instead of exporting the PO4 you binned it into your system. This pooled PO4 will eventually leach back into your system. This is like a time bomb. Similar to having detrius collected at the bottom of your refigium as you've said.

Phosphate leech & algae blooms are caused by insufficient skimming + insufficient water movement so all the detrius that settled down in those blind spots eventually leads to high nutrients in your reef.

[XPeriment 626]

Is the same provided the surface area of the DSB is large enough

But I believe it is quite difficult for those reefer to have a 4ft main tank and 4ft remote DSB tank

For me, I have 2X1.5X1.5 main tank and 2X1.5X1.5 remote DSB tank.

I'm actually in the process of setting up my new tank and I have a 2'x1.5'x0.5' DSB in the sump area for my 5'x2'x2' tank. It might not be as effective as a full DSB but with a lot of matured LRs in the main tank, a good skimmer, some macroalgae and regular water change I think the nitrates can be kept low.

Plus, as per what this thread is about, if the old tank syndrome appears because of nutrient leaching from the DSB, it will be a lot easier for me to restart the sump DSB than if it were in my main tank...just like what Jun Hong said above.

[Jun Hong]

I'm actually in the process of setting up my new tank and I have a 2'x1.5'x0.5' DSB in the sump area for my 5'x2'x2' tank. It might not be as effective as a full DSB but with a lot of matured LRs in the main tank, a good skimmer, some macroalgae and regular water change I think the nitrates can be kept low.

Plus, as per what this thread is about, if the old tank syndrome appears because of nutrient leaching from the DSB, it will be a lot easier for me to restart the sump DSB than if it were in my main tank...just like what Jun Hong said above.

Thank for your support! But your 2'x1.5'x0.5' DSB in the sump area seems too small. However, it is still better than no DSB

[AlfaRomeo]

IMHO, I think DBS/Refuge is no longer needed in our very high-flow, very efficient skimmers that we are employing in our SPS reef-tanks nowadays.

All the crap that we feed will be effectively taken out of the system by the skimmers before they have the chance to break-down and the residual nutrients be countered by the masses of LR we have.

[Ancelot]

Well..yeah i agree with Alfa. A god like skimmer is a must! but too small DSB cant really serve its purpose. DSB gotta be big or else tall... then can serve up to its tip top performance...

[Creetin]

I have never used DSB from the start and probably never will. I think a little sand for looks is good enough.... my tank aint fantastic but i dont see any major problems and can control nitrates easily with a HnS skimmer, lotsa LR, minimum feeding, lotsa flow (1 return, 4powerheads in a 2.4footer), and a denitrator...

I have always tot DSB is a toilet bowl without the flush. Then again i suppose they serve their purpose very well for the first few years?

[Ancelot]

Hahaha.. really good one! toliet bowl without flush Imgaine the poos and the junk left there to rot..

[blueheaven]

Well actually I believe the funtionality of a DSB is still not known up to date and most of us are still unable to maintain a DSB for very long periods as we lack recharge kits, the most important item of all.

I have done an experiment on the effects of creating a totally anaerobic condition and I am surprised that a hell lot of hydrogen sulphide is produced. But what interests me most is that when air is introduced to the setup, after a few days, the black stuff cleared a little. But anyway, I'm still monitoring the setup for a few more days to see of there's any changes.

Going back to DSBs, there are many known setups with long term success so it brings back the question of whether we are doing it wrongly.

Of course we can still rely on our godly skimmers to do the job of removing suspended detritus but speaking of zooplankton population, it certainly does not serve this purpose

[blueheaven]

Hahaha.. really good one! toliet bowl without flush Imgaine the poos and the junk left there to rot..

Well that's why we need the infauna to act as "toilet cleaners" in our DSBs

[IanJ]

I started up my tank almost 2 years ago with a DSB, not my first DSB

Within 6 months or so of setting up i started to get a lot of cyno. Investigation of the DSB lead me to conclude that the expected level of life to make the DSB function was just not there. In light of all the press at that time, I removed the DSB( ok a little bit left here and there)and within a matter of a few days all the cyno had gone.

Not a long term observation or absolute conclusion, but my tank improved so quickly from there. In a few months i will move and re-set up the tank. The bare bottom remains.

[blueheaven]

Maybe we can try to make our own recharge kits?