30g: DSB or no DSB?

[gobies]

Opinions, please?

 

See http://www.nano-reef.com/forums/showthread...=&threadid=3360 for details....

 

thanks!

[tinyreef]

i vote no dsb (>4"). i typically use a msb (1"~3") but some people are allergic to msb

[Sahin]

On my 24G tank I have a 3inch DSB.

I used very fine sand and the nitrates are reducing so it seems to be working. Also the sand is slowly becoming full of critters living in it.

[NaNO ReeFiN]

I'd probably go with a medium sand bed as well, around 2 to 3 inches would be good IMO.

[Dave ESPI]

3 inches no more, no less.. Use 20 # aragonite special reef grade and 20 # LS Get some LS from diferent batches if possible.

makes for more biodiversity.

[dattack]

2 to 3 inches is fine.

[Goofnut]

Dave, what is the smallest tank you advocate using a DSB in? I know you're not a HUGE fan of the DSB, and seem to enjoy the tried-and-true plenum approach, so I was surprised that I didn't see you advocate an SSB or plenum in this case. Is it far enough removed from the "nano" status that a DSB would be acceptable?

[gobies]

Okay, I am not getting even more confused....

 

I've read in several places that 4" is the minimum depth for a DSB. One author specifically recommends against anything between 2" and 4", as you don't get any anaerobic denitrification until you get the anaerobic layer large enough, which doesn't happen with less than 4" of sand. If you have >2" but <4", you start to get die-off in the sand and you don't have enough sand for the anaerobic critters to get going. If you have <2", or better ~1", you won't get the die-off. Or at least such is Calfo's take on the DSB.

 

I've also read that a 40g breeder is about the smallest tank that can actually keep a functioning DSB, as anything smaller does not have a sufficient footprint --> sand volume to keep a sufficiently wide variety of critters. Such is Shimek's view on DSBs in small tanks.

 

SO -- anyone care to refute those points specifically? :-)

 

(BTW, my live sand is from two different tanks that had been established for a year or more. And both of them had been using mud refugiums, which puts some of the mud in the sand. Getting the mud out of the sand is a painful, slow process involving much sand surface stirring and a power filter and a very fine-weave and thick filter pad, and rinsing the mud out of the filter pad every time it gets clogged. NOT something I ever want to do again. At least the sand was free.)

[tinyreef]

i'm not a follower of the 4" rule. if we apply that 'rule' with LR then any rock smaller than 8" in any dimension would not satisfy the 4" minimum requirement (4" from either edge to its deepest portion) and be useless for denitrating. i'll step aside presently on the 4" dsb debate as larger heads butt up against each other (esp. in other forums).

 

i agree the footprint issue is more complicated as shimek alludes to in questioning the ability to sustain a wide enough diversity of fauna. but chances are no captive system would be complete enough then, whether 1g or 5000g, so we would need outside supplements (us!) to hopefully round that out.

 

1" may be a little thin (eating my prior post, gulp ). typical tonga plate rock is comparable dimensionally to a 1" bed though. (hmmm)

 

2"~3" is may be a preferable middle range. most medium LR would compare to those dimensions.

 

sand is preferable imo to LR. it dissolves quicker than LR as it is already pulverized and contains greater surface area than a comparable amount of LR in weight (same concept with carbon or bioballs). it is the additional depth that equalizes its denitrating properties with LR (jury's still deliberating).

[Toyfreek]

Ok,

I was gonna stay out but I hafta say something I guess:)

 

I have seen and serviced all kinds of set-ups. right now in my 35 I am running 2-3 inches CC over a plenum. i have 4" southdown in my nano (7gal bow) and in my 70Gal new setup I have 6" Southdown.

 

The plenum works great *IF* correctly assembled 1.5" eggcrate with nylon screen tightly wrapped around it *With a 4" or deeper oolitic sand bed.

 

The DSB is the same thing. only take out the eggcrate and screen

 

Any sandbed less than 4" I see diatom and hair algae problems eventually. no joke every friggen tank I see with a shallow SB sooner or later succumbs, usually after the first year but sooner for some.

 

Dr. Ron says (and I belive him to be right) that the smallest footprint a DSB would be truley noticably effective would be about the size of a 40Gal breeder (if I remember correctly) But, my nano is hair and diatom free and it uses a DSB? could be luck I guess. or maybe I will see problems down the road.

 

To sum it up, put as much sand in there as you can stand, it is not gonna hurt, and maybe it might actually help....alot.

Next tank for me 12" oolitic aragonite and grass eels!!!

 

sorry about the rambling,

Toy

[Dave ESPI]

I kinda agree with TF, but IME, a PROPERLY set up plennumn is king, yet it is difficult to get a ballance.

 

Goof, a 29 is the smallest I use for a dsb.... anything smaller (cept a 20 xh is pointless. Its all about surface area for a DSB...... oh and hydrogen sulfide dissolution SUX ! (I wont go into it) X)

 

Also, I use a mixed size grain bed. Gas pockets and bed support ( for inverts) is key, as many oolitic and beds are so tight with packing that they will suffocate themselves and in effect "cement themselves" with bacterial actions. TRUST ME ! U DONT want a cemented bed LMAO ! it will cause nusance algaes faster than I can flame a moron ! (J/K)

Gobies, what are U thinking of (or are) using at this point?

[gobies]

I kinda agree with TF, but IME, a PROPERLY set up plenum is king, yet it is difficult to get a balance.  

Could you elaborate on that last bit? I saw the post on making a plenum. Heck, I've even got all the stuff I need to make one.

 

Gobies, what are U thinking of  (or are)  using at this point?

Right now, I have about 2.5" of LS in the "show" 10g, and about 3" of LS in the "fuge" nano. The grain size isn't totally uniform; I can see shell fragments and stuff about 2mm-4mm long/wide. The stuff in the 'fuge is from Whirley's frag tank fuge and is FULL of bristleworms and stuff. (Just went over to measure the sand and counted 15 of 'em crawling around above the sand surface.)

 

Anyhow, the two tanks are getting combined into a 30g long and a 5.5g 'fuge, probably sometime in October. I figure I have enough sand now to do 2" in the 30g and a little in the 5.5g. If I need more sand, I could make a road trip to get Southdown. (I know a source that's about 70mi from my in-laws' house. )

[Goofnut]

I'll have to read some more about the surface area of a nano being insufficient to sustain a viable (and diverse) critter/microfauna population. From what I've read (limited, yet sufficient enough for me to employ what I consider to be a hybrid plenum/DSB design) Dr. Ron and others indicate that continual re-seeding of the sandbed is necessary, even in large tanks, to provide enough diversity to keep the sandbed functional. Would not increased frequency of re-seeding the sandbed in a nano create biodiversity functionally equivalent to that found in a larger tank's DSB?

 

Also, should seeding and re-seeding be done from younger tanks? My thinking here is that the newer the tank (up to a point), the more diverse the population would be.

 

I'm still not sure I follow your point about a 20XH being acceptable, where a 20 or 20L is not, Dave. If I understand the premise correctly, you'd want a higher surface area of sand to water, (sq. inches of sand surface to cubic inches of water volume). Let me know if I'm mistaken here

 

My average sand depth is currently about 2.5", but I had planned for this originally and decided that I would keep adding sand from diverse sources until I reached roughly 3-3.5". That's still the plan, unless I have some major problem with my setup or have evidence directly showing that my setup won't work.

[tinyreef]

dave,

 

the mixed size substrate is what i typically use too. my nano is only sand though (w/plenum, it's an experiment for me ). but you're right i get a much more diverse microfauna population (size-wise at least) using a mixed bed.

[Reefbuilders]

I'd like to say three things. First, shallower bed for finer grain, and deeper bed for coarser grain. Second, IMO, for a typical size (10 gal to 200 gal) reef aquarium, my preference is 1mm grain size of 4" to 6" inches. For example, a bed with 0.5 mm grain can be shallower than 4", and a bed with 2mm grain can be thicker than 8". Third, when thinking what grain and how thick the bed should be, also take into account the kind of sand critters you intend to keep. Finer grain seems to culture smaller critters and vice versa. Hope it helps.

[Toyfreek]

Sand beds regardless of depth should be made up of a lot of different grain sizes from 2 MM down to .25 mm this is generaly so that the larger grains eventually rise to the top and hold down the others, allow for more oxygen at the top layers and critters navigate better in the top layers.

 

I use a mixed size grain bed. Gas pockets and bed support ( for inverts) is key, as many oolitic and beds are so tight with packing that they will suffocate themselves and in effect "cement themselves"

 

Dave,

Oolitic referes to the shape of each grain (oolitic is soccer ball shaped, football for you Brits) Other kinds of sand are to jagged and can harm fauna as they navigate the bed, not killing them per say but inhibiting thier growth and reproduction.

 

Studies have shown that southdown sand is the "perfect" mix of sizes for a DSB or Plenum, and is oolitic in shape. So is caribsea brand as they are both mined from the one source of Aragonite sand in the Carribean. I believe the problem of cementing you speak of is not caused by the size of grains but that Aragonite is Pure CaCo3 exactly what our corals are made of so keeping ALK levels at higher than NSW (like we all strive to do) will cause the Aragonite grains to bond as the free floating Ions are attaching them selves to the grains. (hope that made sence)

 

The point I was making earlier is that a "properly" set up plenum is nothing more than a DSB with a nice screen set up under it. Why then not skip the middle man and just run a DSB?

Good luck,

Toy

[Toyfreek]

I'd like to say three things. First, shallower bed for finer grain, and deeper bed for coarser grain. Second, IMO, for a typical size (10 gal to 200 gal) reef aquarium, my preference is 1mm grain size of 4" to 6" inches. For example, a bed with 0.5 mm grain can be shallower than 4", and a bed with 2mm grain can be thicker than 8". Third, when thinking what grain and how thick the bed should be, also take into account the kind of sand critters you intend to keep. Finer grain seems to culture smaller critters and vice versa. Hope it helps.

 

Reefbuilders,

I wholehearditly dissagree with the above statements for the following reasons:

if you have a shallow bed extremely fine sand is nothing more than silt, just one big anaerobic area, CC would be a better choice.

If you set up a deep bed with coarse sand or CC it becomes a detritus trap, the finer particles allow for the stoppage of settling of detritus at a prescribed depth and may still be eaten by the fauna in the bed in the aerobic zone.

sand critters are introduced through pot luck in your rock (or a detriviour kit) and because you notice smaller or larger is due to comfort of living. using fine sand inhibits the diversity of larger organisms, therefore less bio diversity in your tank. bad IMO.

GL,

Toy

[Dave ESPI]

LOL I dont know who to respond to first.

As I have said this whole sand issue is the "hot button debate"

Perhaps we are all right in some manner......

 

For the "oolitic response.. yes, and NO ! the oolitic sand IS round and smooth, BUT it packs VERY tightly. The chips and fragments are a Necessary reef floor structure supporting component of the reef floor. All the TRUE oolitic sand is produced by Triggers and Parrot fish as they literaly (###### sand) excrete .05 mm reef carbonates.

 

SOUTHDOWN SAND, and Home Depot Sand... this is important...

FLORIDA...... is know ans "the Phosphate capital of the world" for a reason. My divers in Florida are VERY specific as to where they take LS from and they acid test it in a lab before they ship it.

 

GOOF, I HATE ! ALL XH TANKS... Id rather have shallow and wide than Tall and narrow any day. I have some customers who are having problems, I tell them to put in a DSB ONLY so it makes a 20 XH onto a 20 gal tank. I also use a PH on the bottom to push water to the surface.. It makes all the differance in the world to have surface aggitation.

 

REEF, Im sorry, but U are 1/2 correct. TF nailed U.... I think U need to read some more.

 

AND FWIW, I reseed ALL my tanks with awesome LS every 6 months at leat 1 # per every 10 gal of water... I also remove 2 # per 10 gal and rotate the sand to other tanks.. BEWARE OF DORMANT ICH ! it can lurk in da sand and cause issues in tanks that are NOT immune to any particular strain... AND THERE IS A DIFFERENCE ! Not all ICHthosporans or even Irritans, are the same.... ICH LIVES IN EVERY TANK ALL THE TIME ! the fish just are immune ( in good condition) AND they are succeptible to "stress ich".... More on ICH later.

[tinyreef]

i think i've got some corn and nuts in my sand ######! :x

 

sand beds and lights! the politics and religion of the hobby!

[gobies]

Chicago gets enough thunderstorms and snowstorms that I need to be concerned about extended power outages, so the plenum's out.

 

Um. I just realized I have that 15g tower to start up, too...might as well do it all at once! That tank, at least, won't get livestock for a while.

 

Okay...I guess I'll be buying 2 bags of SD (plus more if the locals want some, as long as I'm making the trip anyway).

 

The 5.5g fuge gets a very thin layer LS over maybe a bit of SD; last thing I need is caulerpa getting well-anchored in the stuff.

 

The 15g tower gets 1" of LS and 1" of SD, plus whatever else I need to add to that mix for a jawfish.

 

The 30g tank gets 2.5"-3" of SD and the rest of the LS, which should put the sand bed at over 4".

 

 

Anyone see any flaws in the plan?

[Toyfreek]

For the "oolitic response.. yes, and NO ! the oolitic sand IS round and smooth, BUT it packs VERY tightly. The chips and fragments are a Necessary reef floor structure supporting component of the reef floor. All the TRUE oolitic sand is produced by Triggers and Parrot fish as they literaly (###### sand) excrete .05 mm reef carbonates.

Dave,

oolitic has nothing to do with size it is the shape of each individual grain here's a link to pics under magnification for ya

 

http://reefs.org/phpBB2/viewtopic.php?t=96...ght=silica+sand

notice the varried sizes. the chips and fragments are irrevelant due to the fact that larger solids rise to the top of the substrate in the settling process.

 

BEWARE OF DORMANT ICH ! it can lurk in da sand and cause issues in tanks that are NOT immune to any particular strain... AND THERE IS A DIFFERENCE ! Not all ICHthosporans or even Irritans, are the same.... ICH LIVES IN EVERY TANK ALL THE TIME ! the fish just are immune ( in good condition) AND they are succeptible to "stress ich".... More on ICH later.

 

Well, no not actually,

There are three stages to the ick life cycle: free swimming,parasitic, and cystic. You can't kill the cystic stage that is dormant for a period of time (usually around two weeks)but they will eventually rupture into free swimming, which can be killed either by copper or a total lack of hosts. This lack of host time is said to be at least six weeks, as thier life cycle is shorter but you dont know what stage they are in when you take the fish out so better to error on the long side IMO. after that time there will be no Ich left unless you introduce it again with another infected fish. on a side note it is possible for a fish to have Ich present for very long periods of time and not know especially if there are cleaner shrimp in the tank.

 

 

 

SOUTHDOWN SAND, and Home Depot Sand... this is important...

FLORIDA...... is know ans "the Phosphate capital of the world" for a reason. My divers in Florida are VERY specific as to where they take LS from and they acid test it in a lab before they ship it.

 

I dont really understand this but if you are suggesting Southdown is from Florida you are mistaken, The company that mines this stuff is called Marcona Industries and they import it and distribute it to Carrib-Sea, Southdown, Aragonite.com etc. etc. It's all the same stuff from the same bay in the Bahamas.

GL,

Toy

[Dave ESPI]

Toy, U must know more than me. Take it at face value.......

 

{this is your quote... "Oolitic referes to the shape of each grain (oolitic is soccer ball shaped, football for you Brits) Other kinds of sand are to jagged and......"}

 

-Last I checked NON AMERICAN Footballs were round...

 

As to your ICH reply,

{There are three stages to the ick life cycle: free swimming,parasitic, and cystic. You can't kill the cystic stage that is dormant for a period of time (usually around two weeks)but they will eventually rupture into free swimming, which can be killed either by copper or a total lack of hosts. This lack of host time is said to be at least six weeks, as thier life cycle is shorter but you dont know what stage they are in when you take the fish out so better to error on the long side IMO.}

 

-NO...cyst have a MUCH longer dormant stage.... Tempature plays a major part in this. let your tanks drop to 71 degrees and see what happens over the course of a few days after adding forigen live sand....

 

As to this....

{"It's all the same stuff from the same bay in the Bahamas."}

 

Last I checked the BAHAMAS was off the coast of Florida.. But perhaps U know better than I.....:

 

IME.. Literaly.

[Reefbuilders]

To sum it up, I think a SB with fine grain at the bottom and gradually go coarser upward would be nice.

 

One thing that is true is that I notice my pods and worms seem to dwell only in the coarser sand layer and not the fine grain layer.

[Toyfreek]

Dave,

that is why I was going to let this one go as I do many other threads where 1/2 truths and myth astound me. I did not want to turn this into a P@@sing contest but....oh well

 

If you view oolitic sand under even higher magnification you would see that it is faceted like a soccor ball regardless of overall shape due to the formation of layer upon layer of ions bonding with a nulceus....not parrott fish poop or trigger poop.

from a dictionary of earth sciences:

ooid (oolith)

Sub-spherical, sand-sized, carbonate particle that has concentric rings of calcium carbonate surrounding a nucleus of another particle. See also Oolite

 

 

Florida is Florida.......Bahamas is Bahamas, there is quite a bit of difference due to the US argriculture industry pouring fertilizers down the mississippi and other natural seepage/ runnoff. I would agree that Florida sand is not acceptable if taken near to shore.

 

As for the Ich I would like to see your source as I have always seen the dormant Cystic stage at around two-three weeks before the free swimming stage in Marine heres a clip and a link to explain it better for you.

 

The life cycle of Cryptocaryon is relatively simple. Cryptocaryon is an obligate parasite, one that cannot survive without a period of growth on a fish. It spends five to seven days (at 24 to 27°C) feeding and growing in the skin and gills. The parasite at this stage is called a trophont, and ranges from 60 to 370 microns in size. When the parasite reaches maturity it leaves the fish and enters the water as a large single cell called a tomont. The parasite swims for 12 to 18 hours until a sticky, opaque cyst wall is secreted which allows it to attach to substrates such as rock, coral, or glass.

 

These cysts measure from 200 to 400 microns in diameter and can sometimes be seen on surfaces inside the aquarium. The cells divide within each cyst to produce up to 200 daughter parasites called tomites. This multiplication process takes anywhere from 3 to 28 days (Colorni 1985). The tomites are much smaller (25 to 60 microns) than the original cell because they result from its cell division. They produce cilia which allow them to bore through the cyst wall and emerge into the water. These free-swimming cells are the infective form of the parasite called theronts. They are very small and not easily seen by the naked eye at this stage, and survive for only a few hours unless they find a host. When the theronts encounter a fish, they burrow into skin and gill tissue where they begin to grow, thus completing the life cycle.

 

The metabolic activity of Cryptocaryon is affected by the ambient temperature of the water. The warmer the water, the faster the parasite grows, thus speeding up all stages of the life cycle.

 

Ich is not present untill you introduce it into your system. here's the link:

 

http://www.breeders-registry.gen.ca.us/Rep...sumr/crypto.htm

 

 

It's not that I am smarter, or know better I just do some research before I give out advice...shees

I never insulted you or asked for your credentials, so please continue our discussion in a sensible manner and I'm sure we can find lots of common ground we do agree upon, and some we do not.

Peace,

Toy

[tinyreef]

...and everyone wonders why Hebrews, Muslims and Christians fight over the same God.

 

topic, topic. gobies's always causing trouble!

 

i'd go with fine sand with some cc mixed in, min. 1" to a max. of 3" imho.