DSB w vs w/o Plenum

Reef Aquarium & Tank Building Forum

Help Support Reef Aquarium & Tank Building Forum:

In working with DSBs for many years now, I really just don't see the need for plenums, plates, drawing water from below, etc.

I have dismantled (to move) 5 and 8 year old DSBs, and marveled over how clean the sand was... as if it had been installed the week before.

The premise of "needing" to periodically draw waste from below is flawed IMO. The waste should not be there in any significant amount if the tank has had proper water flow all along. Aquarists that have been to reefs appreciate how extremely dynamic even the calmest reef is. And when you have enough water flow in the aquarium to keep solids in suspension, then the substrate does not become a nutrient sink. Rather... the infauna in the bed are rate-limited by the frugal admission of particulates to the bed with enough water flow for DSBs.

Keep it simple my friend... a static DSB and good coral growin' flow if the use of substrates appeals to you :)
 
anthony, i do like the looks of a sand bottom but i run a barebottom in my tank. If I did want to switch to a dsb, what would your suggestions be on the depth of the sand bed? what substrates should be used? what should the amount of water flow be over the sand bed and what should the maintenance of it be? i have always been leary on dsb's and am hearing alot of pros and cons. hopefully you could help another pennsylvanian to learn this awsome hobby....lol steve
 
I see your points, Anthony...

I do use a DSB...my sandbed is right around the 5 year old mark, give or take, and I have moved the tank twice with the DSB intact...so far the sandbed has functioned beautifully...I could however use some more flow...a situation I plan on correcting when I move the contents of my current tank to a larger one this spring.

MikeS
 
all good Mike/all... indeed the discussion itself is productive and helpful to consider/re-examine notions.

As for what is enough flow: look to see that detritus does not accumulate... patches of diatoms on the sand don;t linger... cyano slime algae (although in and of itself it not that bad/big of a deal... its presence is indicative) does not persist, etc. All indications of inadequate flow in most cases. And do simply look to see that movement (polyps waving, particles flowing by, etc) is brisk.

Few tanks can get by with less than 20X turnover. Acro tanks and like sps displays may require 2-3X that (40-60X turnover per hour).

Its really hard to have too much water flow in a tank... rather the wrong kind at times (excessive laminar flow as from powerheads, streamers, or unteed sump returns).

This is largely the motivation for closed loop manifolds. They are cheap and easy to build, and give great options for finessing flow from many different points to stimulate coral growth, and reduce dead spots for flow.
 
In the larger tank, I'm planning a closed loop type system...but it will be irregualr shaped to follow the bask side of the rock aquascaping and primarily on the back and bottom back of the tank, blowing the water through the rock and towards the front of the tank...

MikeS
 
I hear people saying that a sand bed within a smaller tank would not be usefull other than for asthetics. At what time or in a specific size tank does the dsb start to become beneficial? is there a given footprint size that it has to be?
 
I have always heard that as well, but it doesn't make much sense to me...after all, if the size of the sandbed in say a 20 gallon tank is proportionate to the amount of rock, water and livestock as it would be in a larger tank, then what difference does the actual size make? As near as I can guess, unless for some reason the actual dimensions of the smaller tank somehow effect it, size should be reletive...perhaps somebody can enlighten me on this concept... :D

Is that like a oxymoron???
Ok everyone back to singing kumbayaaa


Mike
Click to expand...

:lol: bacteria are reducing nitrate o Lord, Kumbyaa... :lol:

I know you love a good sandbed thread, mojo my friend... :D

MikeS
 
I would agree with Mike a DSB is going to be sized to bioload, not the size of the tank. I believe the proportions according to the dsb experts are 3 to 4 small fish in a 90 gallon tank with a 6 inch bed.

Mike thier is nothing static about a DSB, if thier is I surely would like to know, lol.

Mike
 
mojoreef said:
I would agree with Mike a DSB is going to be sized to bioload, not the size of the tank. I believe the proportions according to the dsb experts are 3 to 4 small fish in a 90 gallon tank with a 6 inch bed.
Click to expand...

That's the way I see it...the bioload is the main limiting factor, not the actual physical dimensions of the bed itself as a function of tank size...

mojoreef said:
Mike thier is nothing static about a DSB, if thier is I surely would like to know, lol.

Mike
Click to expand...

That was Anthony :D ....and I believe he was using the term "static" to mean without mechanical assistance under the sandbed, like a UGF or our active plenum idea... :D

MikeS
 
quite correct... "static" merely in the sense that it does not need water forcibly moved through it like an undergravel filter. No plates/plenums, etc.
 
they are very fine to run in smaller tanks for how affordable/easy it is to provide adeuate water flow above the bed. At the very least, in such applications thay are cheap and effective denitrifying vehicles. I have one in my 11 nano, 50 gall fuge... 50 gall display, etc.
 
guys, when you say 3or 4 small fish in a 90 do you mean the dsb will start to break down if more fish are added? I see alot of people with dsb's and have quiet a few fish..larger tangs included. does this mean thier sandbed is inadequet for the load? does that also include invertebraes as well? my tank at this point has 1 ocelaris, 3 chromis, sally lightfoot crab, emerald crab, peppermint shrimp, cleaner shrimp, some snails hairy mushroom and star polyps in a 140 gallon tank. If i had a dsb, would it be at the point of being overloaded if I was to add a couple more fish? I believe at this point I am leaning more twards a mixed reef with lps,softies and fish. if i plan to add more fish would it be more beneficial to leave the tank a barebottom? i dont want something as a dsb breaking down leaching nitrates or phosphates back into the tank. it seems like there is a real fine line when it comes to the dsb's. i do love the look though. :confused:
 
quite correct... "static" merely in the sense that it does not need water forcibly moved through it like an undergravel filter. No plates/plenums, etc.]
Click to expand...
Ok, :p

Sryder I dont know its a Dr. Ron thing, The concept is that it takes alot of bacterial systems to process waste, Ron came up with that number as a guideline on hwat the dsb could do. If you go more then that then the dsb is going to have a hard time keeping up, which would eventual overload.
Anthony's concept (if I may :D ) is to do everything a person would do with out a dsb (ex: heavy skim, ozone, latos of water flow) but to use the bed as a complimentary filtrations system and a place to grow bugs.

Anthony you want to stay at the ranch in April???


Mike
 
hey mojo, i guess my biggest fear of a dsb is that eventual overload. i know i dont have to tell you, i have seen your pics. the time, cost and everything else that goes into setting up and maintaining these systems is somtimes overwhelming at least to a beginner. i just dont want to get to the point that im tearing it all apart because of something like leaching from a sand bed. i understand that the dsb is complimentary to the live rock and skimming. if the sand bed breaks down, would that be enough to compinsate for the breakdown?
 
Sryder I view DSB's differently then most on this forum. I look at them as purely a biotype type of filtration. To be used only with corals that perfer and can handle heavier loads of nutrients. If you practice good husbandry (ex: good flow, dont over bioload or feed, skim well and possibly the use of ozone) you can maintain a dsb for an extended period of time and reep some side benefits. I have seen a number of DSB's implode but it was usually tied to the human factor (power outage, meds and so on). Most folks quite them due to not doing the above husbandry and thinking that the dsb can do it all by itself, or they get tired of the algae blooms.
So if you can work with in those parameters and you truely like the dsb then by all means give it a shot.

not sure if that answered your question???


Mike
 
April? You're scaring me bro... I have you/us penciled in for the second week of May (14th ish)?

But I would love to stay with ya if you have the room and can put up with me <G>
 
thanks mojo, I think you said it right. what would you reccomend as a substrate? I also must say seeing pics like yours and others on this board is awe inspiring at least..... keep up the good work it is truly appreciated....
 
ooops sorry Anthony my bad on the date, and the door is always open.

Sryder I practice a different way of dealing with waste and detritus, I take care of it right away and dont do the aquarium composting thing, so or me I dont use a substraight, unless layers of corraline could be called a substraight.


MIke
 
You must log in or register to reply here.
Back
Top