Jump to content

DSB or BB?


Anemone
 Share

Recommended Posts

  • Replies 55
  • Created
  • Last Reply

Top Posters In This Topic

  • SRC Member
zephyros, i think in order for a SSB to work, still need to have enough current to lift the detritus off the sandbed and that usually involves more powerheads(more heat) and also the likelihood of sandstorming. I agree too with the biodiversity but i guess what our local community lacks is Sandbed recharging kits, which i guess is what is required in order to make sandbeds viable for natural filtration.

not true, I'm having a SB with 1 PH in it. that's where the cleaning crews

comes in ... (always prefer them to chemical control) rememeber the

starfish, cucumber, snails, hermit crabs, blenny, goby, shrimps that u have put it ...

they are more than just viewing pleasure :P

also, if u have design properly, your overflow should be drawing water

from the bottom of the tank as well, not only for skimming the water surface

:P

Link to comment
Share on other sites

  • SRC Member

just read about Paul B's reverse UGF method...sounds good but i think i will stick to what i have, thanks for sharing something truly unique madmac.

zephyros whats your tank dimensions and how long have u been running it? Any algae problems so far? Would like to know just to serve as reference. Anyway i was thinking more of infauna rather than macro sand sifters like starfish or cukes, more of copepods. The pod population i think decreases with time due to predators and after awhile the sandbed becomes barren i think.

So what's your setup anyway zephyros? a SSB but with enough current to sweep the detritus off the sandbed meaning your sandbed is purely aesthetic? or is it serving some purpose to you? Any deadspots where all the fish and snail poo gather?

Sorry if it seems like i'm asking in an offensive manner coz there are no offensive intentions, just trying to draw conclusions from other peoples' setups since when it comes to DSB and BB maintenance, there's always some gray areas that i can't resolve from all the discussions i've read so still trying to draw more ideas.

Thanks all :D

Link to comment
Share on other sites

  • SRC Member
zephyros whats your tank dimensions and how long have u been running it? Any algae problems so far?

tank size L4xB2.H5x2

Algae problem comes and go. I believe my algae problem is likely due

to the heavy feeding of my anthias, 2x a day, cearting a very nutrient rich

system. Algae on the glass I clean, algae on the SB i leave it alone, after

a few days, it will be clean as the crews eat or shift through the sand.

Anyway i was thinking more of infauna rather than macro sand sifters like starfish or cukes, more of copepods. The pod population i think decreases with time due to predators and after awhile the sandbed becomes barren i think.

There's various stage of breakdown. Each crew had its place in the the food

chain. identify what is ur tanks need and get the correct crew. eg i am feeding

heavily, so i had to crews to eat the left over food that had sunk down to the

SB. starfish/shrimp/hermits/certain snails/crab will do it. Need to control algae,

then snails/hermits/fish/urchin/crab (depending on what algae). Need to shift the

sand and clean up further, cuke/snail/signal goby :P

So what's your setup anyway zephyros? a SSB but with enough current to sweep the detritus off the sandbed meaning your sandbed is purely aesthetic? or is it serving some purpose to you? Any deadspots where all the fish and snail poo gather?

No i leave the detritus where they are. molt fr shrimp and crabs etc

the SB in a way is aesthetic, as a SSB does not really serve any function

as compare to DSB. Deadspot, depends on ur landscraping

this cleaning crew concept will apply to keeping the DSB clean as well.

I am too lazy to set up a DSB, and there are too many conflicting opinion

on DSB. But a BB looks to fake for me.

cheers

Link to comment
Share on other sites

  • SRC Member

hi there bros,

i think the decision whether to go BB or DSB or SSB will largely depend on the type of critters one intends to keep, and not that any one system inherently is better. i mean, for a sps dominated system, BB is great, but i doubt LPS and other less flow loving corals will appreciate BB conditions as much. Likewise, if you wish to keep sand- dwelling creatures, and corals who's diet incorporates alot of bacteria, like dendronepthya, then the DSB will probably be best. not to disagree with bro weileong though, as i agree that SSB is the less desirable of these three systems, but i think the SSB may also be useful if one utilises macroalgaes in a refugium for nutrient export, because the SSB will facilitate the breakdown of everything to nitrates whilst not really enabling this nitrate to further break down into nitrogen and oxygen. this might nnot sound like a condition to have, but with a macroalgae fuge, it might just work wonders (due to the redfield ratio explained further down).

the problem i find with the DSB is that it breaks down nitrates too well- i always get undectable nitrates, whilst i still get a little measurable phosphates- 0.03ppm thereabouts. what happens then is that the macro algaes in my refugium are nitrogen limited, so even if they potentially have the ability to bind phosphates, they dont, because there isnt enough nitrates for their growth. according to the redfield ratio, marine algaes utilise 16-22 molecules of nitrogen per every molecule of phosphate, so for macroalgaes to grow, the ratio of nitrates to phosphates needs to be at least 16:1, inorder for the macros to be able to bind all the phosphates. for illustration, take for example, the ratio of nitrates to phosphates as being 16:2, what results is that due to the uptake ratio of 16:1, after the macroalgae has grown as much as it can till limited by nitrates, there is still one unit of phosphates left. this is the reason some on RC have taken to dosing nitrates to bring phosphates down. it may seem counterintuitive, but makes sense if you think about it.

in my tank, even though i ran rowa and phosguard, i still always had 0.02-0.03ppm phosphates, and undetectable nitrates, so my marcos grew, but very slowly. diatoms grew faster. the thing is, cyano and diatoms are able to use nitrites (NH4), whilst macros are only able to utilise nitrites if first presented with nitrates (facilitating nutrient), so in tanks where nitrates are super low, with abit of phosphates, nuisance algaes like diatoms will flourish because they are able to use nitrites before they even break down to nitrates, thereby outcompeting the macros.

with BB, unless flow is super, i think nitrates will rise over time, so i plan to balance this by having a refugium area for growing chaeto to help take up the nitrates. hopefully, what makes sense in theory works out well in practice ya.

Its nice to hear from bro weileong that making the ocnversion to BB without cooking yoru rocks didnt cause big issues with time, but i think the zeovit system probably helps with that as its bacterial driven. I think i'll be going BB without cooking as i actually like the look of macroalgaes in my tank, just not nuisance algaes. but the look is what i have to get over la. i like the look of sand. sigh.....

anyone tried the faux sandbed thing??

Link to comment
Share on other sites

  • SRC Member

so ian, tell me if i'm summarising what you mean correctly. What you're saying is that DSB whacks the nitrates, which means insufficient nitrates for your macros to absorb phosphates as well. which explains your 0 nitrates but presence of phosphates hence ur problem algae?

Hope I understood that correctly. Also, i think a part of BB maintenance is to suck out water detritus and poo is at the bottom of the tank, so i think coupled with a good skimmer, nitrates should theoratically not rise at all.

Conducting a mini experiment in my nano which basically consists of green yumas, a BTA and a ocellaris pair. currently running liberty with constant sponge maintenance, airstone skimmer and small powerhead to blow detritus around. layer of sand is purely aesthetic, about 0.5cm

I guess an oversight on my point too is that softies generally do better in water with abit of nutrients rather than super clean waters for sps. Note i mean this generally coz some guy in RC got flamed for saying all sps need super clean water. whether or not this is the case i'm not sure. But you guys get what i mean

Link to comment
Share on other sites

  • SRC Member

hi dreamzcape,

ya, thats what i meant. i mean, inorder for macros to be able to bind phosphates, they have to grow, and they need both nitrates and phosphates inorder to do this, in the ratio of roughly 16 nitrates molecules to every phosphate molecule. so with the DSB i was running, my macros were persistently nitrate limited.

nuisance algaes ensued because nuisance algae like diatoms and cyano are able to utilize an alternative nitrogen source to nitrates, that is, nitrites directly, so they are a step in front of the macros in that sense, and grab the nitrogen in the form of nitrites before it breaks down to nitrates. most of this is discussed under the redfield ratio discussions on RC.

Also, i used to feed huge amounts of phyto, so thats my phosphate source. if i didnt do that, all this would be less of a concern.

cheers,

ian

Link to comment
Share on other sites

this thread got pretty lively. anyway, im going with a sandbed. not really deep, but i see my worms burrowing in after getting flushed out when i poured the old sand in.

regarding sandbed fauna/cleanup crew, u guys know where to get them cheap? i find that they come at cutthroat prices despite their size.

jon.

Link to comment
Share on other sites

  • SRC Member

yea i'm glad it got lively! infact i feel that the more people share the opinions, we can have a better idea of what we want to do with our tanks. As for me, haha, still not sure what to do man seriously.

I want to be rid of nonsense algae and yet at the same time keep some softies and it's like asking abit of both worlds kinda....still wondering if an 820 is gonna be big and ugly in a 2 x 1 x 1.5, not sure of my ability to conceal it yet make sure it generates enough current.

Link to comment
Share on other sites

  • SRC Member
this thread got pretty lively. anyway, im going with a sandbed. not really deep, but i see my worms burrowing in after getting flushed out when i poured the old sand in.

regarding sandbed fauna/cleanup crew, u guys know where to get them cheap? i find that they come at cutthroat prices despite their size.

jon.

Hi, what are the sandbed infauna/cleanup crew that you saw at cutthroat prices?

i dont know anyone offering worms/pods locally ..hmm..

Link to comment
Share on other sites

  • SRC Member

Since we are on this topic, just want post an idea to see if reefers here agree or not:

If going BB on the display tank, try to use minimum rocks in the main tank and allow for more flow and also less LR shedding/detritus settling on the bottom of the tank. For the NO2/NO3 denitrification, use a remote sump or a sump that is large enough to house all the necessary LR. Now here is the idea: Cover up the sump to make sure that no light is penetrating it and then the LR will be more or less bacteria driven, just like in the LR cooking process. Less problem with algae if one's nutirtents are high, only if. :) . In the section of the sump where the LR is to be placed, make all the LRs sit on a platform with one end accessable so that maintenance can be done by siphoning all the settled detritus by inserting a hose.

Link to comment
Share on other sites

Hi, what are the sandbed infauna/cleanup crew that you saw at cutthroat prices?

i dont know anyone offering worms/pods locally ..hmm..

well, i dun see pods for sale. i just meant the really small hermits n snails. the last time i saw one they were selling for 2 digit prices. (10+ - 20+) EACH.

jon.

Link to comment
Share on other sites

  • SRC Member
Since we are on this topic, just want post an idea to see if reefers here agree or not:

If going BB on the display tank, try to use minimum rocks in the main tank and allow for more flow and also less LR shedding/detritus settling on the bottom of the tank. For the NO2/NO3 denitrification, use a remote sump or a sump that is large enough to house all the necessary LR. Now here is the idea: Cover up the sump to make sure that no light is penetrating it and then the LR will be more or less bacteria driven, just like in the LR cooking process. Less problem with algae if one's nutirtents are high, only if. :) . In the section of the sump where the LR is to be placed, make all the LRs sit on a platform with one end accessable so that maintenance can be done by siphoning all the settled detritus by inserting a hose.

i think it would work but still...the liverocks need to be cooked? Coz in the end whatever nutrients leech out from your LR in your remote covered sump will still go back into the main tank where there is light, hence algae problems will still occur. That's my stand on it.

If cooked rocks were used in the first place, then most of the nutrients have been leeched and algae gone, so becoming purely bacteria driven.

Anyone else has other opinions?

Link to comment
Share on other sites

  • SRC Member

WS, then it shd work no different from canister filters...the trouble with remote refigiums, whether SB based or rocks based or other filter medium, as long as there is a place where detritus can be trapped and rot, is you'll get phosphates. So while your first part makes absolute sense, the second deserves greater maintenance for it to work well.

So while the whole grain in the BB.... is to effective/efficient remove detritus, or nitrogenous compounds before it require de-nitrification to take place.

These two pages are extremely insightly and they seek to explain why/how bacteria + pypto can in-corporate N+P in their bodies for skimming to export.

Link to comment
Share on other sites

  • SRC Member

dreamzcape,

The rock to be used will still have to go through the cooking process in the beginning when they were bought from LFS.

madmac,

You mean that if all the LRs were in the main tank, you will not get shedding/detritus? You will still need to do maintenance, abet much more difficult if siphoning in the main tank. So maybe you can elaborate more on your statement :

'So while your first part makes absolute sense, the second deserves greater maintenance for it to work well.'

You will be surprised that my rock curing tub that was in place for 1 year waiting for my main tank to be up, the LRs still shed detritus. <_<

Lets admit, be it there is shedding or not, with livestock like SPS,LPS or whatever, even only LRs, there is bound to be PO4 generated due to respiration. Do not believe? Come and measure the PO4 in my tub even I have a AP850 skimmer and PO4 is still generated, I still have to run RowaPhos, even NO3 is still detectable. Maybe if I run Zeovit in the tub, then things may be different.

IMHO, do not get too hype into believing that with a over-powered skimmer, you will end up with zero PO4 and NO3. One still need some form of measures to consume all these PO4 and NO3, be it DSB or Zeovit. A skimmer, even over powered ones can never keep up with the natural process of respiration. :)

Still not convince? Try using a super powerful skimmer and not do any water change for 2 to 3 months and observe what will happen to your livestocks and also your tank. :D

Link to comment
Share on other sites

  • SRC Member

welll, yes its only that you can't get that sort of massive random flow in a refugium...(well you can but it'll be a waste) to sweep off the shedding that you can in the main tank.

Shedding per say is not the concern here at all, ...yes it will shed(leak/leach) when it gets full to balance out with the cleaner water column... the concern is the trappings you'll get, as it acts jus like a filter medium.

I've tried this, using the smaller rocks I cooked, put them in a canister filter inplace of the normal layered style type. I still go thru' the regular maintenance of 1 month cleaning the canister. The rocks inside have no algae(they can't) but it gets just as diirty for the trappings, not shedding.

So to answer your qs on a remote refugium/sump filtration...jus sharing with you what bomber does, in his sump. In the first section, skimmer. It picks up what goes in from the main tank, and returns to the second middle section where he places an egg-crate on the sump floor. The egg crate catches the things that escapes as it settles... there it is left for easy syphoning out.

The fisrt part will work as it doesn't require the denitrification process at all... meaning you don't need plenty of rocks, not even big ones is needed(this is not to say big rocks are bad, they are atucally very good).. you design the flow + skimmer to take care of it

wl, if the rocks are still shedding after 1 yr of cooking then something not done right, they should stop. I've seen rocks cooked but still shed, wif crabs inside, they sort of bite off the inner parts of hte rocks for food and cause the shedding of sand-like stuff. Also maybe certern type of rocks are more prone to corrosion... not sure on that.

big power skimmer...well they work, it jus rt-sizing thats important and wet-skimming. PO4 is not what you want in there, if it gets absorbed, it will be released later.

Link to comment
Share on other sites

  • SRC Member

bacteria will colonizes any surface where food is. In our tanks they are limited by space, not food. Anaerobic bacteria are able to store 'food', in case there is a short supply, they will use it up... this explains why even with nutrient poor, pristine water conditions, bacteria still lives for months on end.

Bacteria tugour, pressure is a like a battle ground where both Anerobic + aerobic slog at each other for more space... the more cleaner the rocks(ie. more O2 can enter) and the aerobic will gain more ground, the less O2 and the anerobic gets more space. The thin line that separates the two is anoxic region.. that where the battle takes place. The dead will litter the 'ground' and be release back as phosphates to be consumed as food. This dead bacteria, can also be regarded as detritus... eventually you will reach equilibrium, with each water change you do, the rocks becomes cleaner and cleaner. Eventually that battle is even, ie. it cannot get any cleaner, the region 'lines' are drawn and there are is very little dead, to the point you dont' notice anything.

it works, I've tried it with set of small rocks... absolutely clean.

Link to comment
Share on other sites

  • SRC Member
it works, I've tried it with set of small rocks... absolutely clean.

I have a 2ft quarantine tank that was BB with some small pieces of rocks. The tank is empty for more than 4 months and still running so that anytime ready for use if needed. The small rocks are coming to 2 years old and believe me, they still shed detritus. Well, maybe your conditions are different from mine.

Link to comment
Share on other sites

  • SRC Member

well, i dun see pods for sale. i just meant the really small hermits n snails. the last time i saw one they were selling for 2 digit prices. (10+ - 20+) EACH.

jon.

oh dont worry..they dont really make good sandbed cleaner.. its purely for cosmetic IMO..

bristleworm is good enu

Link to comment
Share on other sites

  • SRC Member

back to the rock cooking issue...in my very own personal opinion, i think if done correctly, SHOULD not shed since everything else is suppose to die off except the bacteria.

BUT i have read that there are pods and coralline algae that survives the cooking process, which means that stuff like rock worms might still survive deep in the rock.

Hope you guys know what kinda worms i mean, read some words live in the rocks and all u can see is small holes where rock material is slowly purged out, like something spit it out.

Link to comment
Share on other sites

  • SRC Member
back to the rock cooking issue...in my very own personal opinion, i think if done correctly, SHOULD not shed since everything else is suppose to die off except the bacteria.

BUT i have read that there are pods and coralline algae that survives the cooking process, which means that stuff like rock worms might still survive deep in the rock.

Hope you guys know what kinda worms i mean, read some words live in the rocks and all u can see is small holes where rock material is slowly purged out, like something spit it out.

There is actually more living things inside of the rocks than one expected. Again, do not be surprised to see crabs surviving even after months of rock cooking, meaning months of total darkness. So, worms and others living forms will survive.

I have even sponge, tunicates growing out of the cooked rocks even they were scrub clean of them before cooking.

Link to comment
Share on other sites

  • SRC Member

There is actually more living things inside of the rocks than one expected. Again, do not be surprised to see crabs surviving even after months of rock cooking, meaning months of total darkness. So, worms and others living forms will survive.

I have even sponge, tunicates growing out of the cooked rocks even they were scrub clean of them before cooking.

yep yep..that's exactly what i was getting at. Meaning that sometimes it's not totally up to us whether the rock is totally purged.Therefore i guess it is possible to exist a situation where the liverock is totally bacteria driven but with still surviving crabs and livestock.

Which means still more rock shedding in main tank ;) ...no system is perfect anyway right?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share




×
×
  • Create New...