BB Reef! Substrate y/n  6/7/07
Guys!
<Hello>
Just a short sweet question? Is it better to keep a bare bottom Reef than having the coral sand below it? Thanks in advance.
Regards
<While there is a lot of arguing on many of the reef forums, I much prefer a sand bed, both for how it looks and what advantages it offers. This does not necessarily mean a DSB, although that is what I use. A shallow sand bed, less than 1 inch, also can work.>
<Chris>

Substrate... to Use or Not to Use, That is the Question    2/16/07
<Hi Brent!  Mich here.>
  I went to my LFS the other day.  I am starting up a FOWLR system in the range of 230g to 300g.  I may just dedicate the whole system to the clown trigger.  Or I may go in another direction when it comes to fish selection.  I have asked advice from your website before and found it very beneficial.
<Glad to hear.>
  The man working at my LFS said that in a FOWLR system he would recommend going with no substrate.  He said that the substrate will trap nitrates and this causes the nitrate readings to spike.
<Depends on your setup.>
  He also told me that no substrate acts as a good pH buffer.  
<Some substrates do assist with pH buffer others do not.>
And no substrate is easier to maintain.
<Depends.>   
  I personally would really like substrate.  
<Then use a substrate.>
I believe that it would help the fish feel more at home.  
<Quite possibly.>
I also like the way it looks in the aquarium.
<Yes.>
  What would you recommend?  
<I would recommend reading here:  http://www.wetwebmedia.com/marsubstr.htm  >
Can the fish behave normally with a bare bottom tank?  
<Some can, some can't.>
Would a bare bottom tank cause undo stress on the fish?
<Depends on the fish.  Many wrasses bury themselves in the sand at night to sleep.  Jawfish need deep sand beds in order to build a home.  For many other fish, the substrate is immaterial.>  
  Thanks for you time
<You're welcome!  -Mich>  
Brent
<p.s. Next time please use proper capitalization!  I not i, please.

Thumbs up or thumbs down?  9/6/06
Dearest Bob.
<Heeee! Call me Caesar!>
I would just like to have your current take.  I am setting up a 90 with 55 sump.
For the moment I would like a heavy bio loaded fish only.
I was thinking remote 10 inch sand bed in 55 sump but bare bottom display.
Just wanted to know your vibes towards this or would you go for DSB in sump and DSB in display as well..?
<I'd put just some... an inch or less substrate in the main tank... and remote the DSB as you state. The gravel for disallowing reflection...>
Thanks Bob. Your reaction will influence me directly.  You're the god of my tanks.
Tristan
<Actually... I'm more like a/the prophet... and you're the god... Buddha Bob>

Re: Saltwater tank problem  9/10/06
One final word on this. Do you think it is possible/advisable to run the tank without gravel or is there a need to have at least some type of media
on the bottom. Thanks for your time. Tom
<<Tom:  Many people who try to grow hard to keep SPS corals swear that it is easier to keep them in a bare bottom tank.  In all other situations, it's mostly a matter of personal preference.  In the saltwater world, most people don't add gravel to their tanks.  They usually use sand. What type of gravel is it and where did you get it from?  If it is something that is not normally found in an ocean environment, it might be contributing to an increase in phosphates and nitrates in your tank.  Best of luck, Roy>>

Re: Saltwater tank problem  9/10/06
Thanks for the fast reply. Forgot to mention that I had the brainstorm to set up the tank without any gravel thinking that it would keep the tank cleaner. Any idea if this may have had a hand in my troubles? I've since added gravel.
<<Thomas:  Did you note the problems after you added the gravel?  If so, the cloudiness could have come from dust that was on the gravel.  I would suggest keep changing the water and testing the parameters.  Depending on what it is made of and where it came from, some gravels can add to your phosphates and help increase your nitrates.  If it is a fish only tank, nitrates shouldn't be too much of a concern.  Best of luck,  Roy>>

Sandbed Confusion?
Hello Crew,
<Hi there! Scott F. here today>
I've had numerous tanks throughout the years with the same results, everything would be fine for the first 3 months then after that green hair algae would start growing and by 6 months the tank would be covered in green hair algae. This seems to happen in all the tanks I setup even though I do water changes, add higher flow rate, reduce feeding, reduce lighting, etc, etc. It always seems as though my sandbed is a phosphate sponge even though it was between 4 - 5" deep in all these tanks.
<Well, initially, as you know, nutrients accumulate in systems regardless of sandbed depth, since the nutrient export processes in new systems are immature and cannot handle the large influx of nutrients. I guess it's a "right of passage" in many systems, and does go away with good husbandry>
Now I'm setting up a 240 gallon tank as a FOWLR and was thinking of going bare bottom so that I could easily siphon out all the garbage from the bottom of the tank and avoid it breaking down and creating phosphates. I was going to sprinkle a bit of crushed coral for decor since I don't like the plain glass look, but I've inherited a banded cat shark therefore I'm afraid that the few pieces of crushed coral will cut his abdomen, which leaves me with either using starboard (plastic) or going completely bare bottom.
<Personally, I don't like the bare bottom look, but many hobbyists seem to feel that this is an easy way to keep maintenance tasks easier. On the other hand, this is similar to the concepts used in the 80's and early 90's, in which no sand bed was favored because it was thought that this would assist in maintaining a "cleaner" system. This school of though fell out of favor when the "natural" philosophy became popular. One of the big negatives of the bare bottom technique is the potential accumulation of nitrate, as well as some lack of chemical stability (calcium levels, pH, etc.)>
Some people have suggested that I put a 1/2" of sand,  but I'm afraid that if I do this, I'll end up with Algae yet again since I won't be able to suction out the detritus.
<I don't think that you are any more likely to experience algae problems with a 1/2" sandbed than you would with a bare bottom. detritus will accumulate over time, but should not be too much of a factor if you are attentive to maintenance>  
Sincerely,  A Frustrated Algae Plagued Fish Keeper.
<I can understand your concern and confusion. One only has to surf the message boards out there to see hundreds of different points of view on the issue of sandbeds. The important thing is to consider the requirements of the animals that you want to keep, the maintenance practices that you want to follow, and go for it. I think that consistent husbandry practices are as important as any methodology that you choose to follow. Good luck! Regards, Scott F>

Back To The Future? (Bare bottom Tanks And UGFs)
Two questions:
<Sure>
Is there any benefit to using a UGF with reverse flow utilizing crushed coral as a substrate?
<Well, reverse flow undergravel filters were all the rage in the late seventies and early eighties, before wet/dry filters and sumps came into vogue. They fell out of favor when more "complete" biological filtration systems and techniques came into being. UGF systems certainly are efficient biological filters, but they tend to trap detritus and organics over time, and will slowly drive down the pH of a system that employs them. In the end, you're really better off using the simple sump systems that are very readily available and easy to run>
What are the pitfalls of a bare bottom tank?
Don
<Well, Don- in a nutshell, the real pitfall of a bare bottom tank is the lack of denitrification processes. I don't want to oversimplify things, but it essentially boils down to that. A sand bed-preferably a deep one- will foster denitrification processes that can greatly improve water quality. Tanks without sand beds tend to develop accumulations of nitrate over time. Yes, there are some detractors of DSBs on the popular message boards, and a few people are trying to go "retro" back into the bare-bottom "Early Berlin" style of the mid eighties. They tout the ease of being able to remove detritus from the tank, the "cleaner" look, etc. I'm a bit puzzled as to why people want to go back to a technique that really didn't work that well in the eighties...Personally, I think that the new bare bottom trend is just an excuse for running super-powerful pumps without worrying about blowing sand around! Aggressive protein skimming and good husbandry- mandatory for any successful system, are crucial in bare-bottomed tanks. I sincerely believe in my heart that a well-maintained tank with a decent sandbed can run for years and years without problems. Do get different opinions on this, of course. Good luck! Regards, Scott F>

Alternative to a DSB and BB
<hello>
I'm in the process of setting up a 75gallon FOWLR (reef safe fish only) to be slowly converted over to more of a reef setting over time.  I've searched all over the place for this, but I get so many diverse and inconsistent answers that I just wanted to ask someone directly.
If one does not want to do a DSB or a bare bottom tank (for lack of space in the tank or aesthetic reason, whatever), how many inches of substrate should one use,
<1-1.5 inches>
what type of substrate would be most recommended and what size grain?
<I like live Fiji white sand (to save money you can mix with a dry sand)>
  And then with a more shallow bed, how should one go about maintaining it properly?  Would siphoning out this more shallow bed more regularly lead to pulling out a great deal of the sand as well as the detritus?
<yes once in a while vacuumed the sand lightly. After you vacuumed the sand into a bucket rinse with fresh water to remove any dirt/detritus and the add the cleaned sand back into your tank. You can also buy some dry sand to add in after water changes.
Should additional sand be added after every few cleaning to keep the shallow bed intact.
<yes MikeH>
thanks for any info.

Re: alternative to a DSB and BB
A quick follow up please.
<sure>
Is live Fiji sand an aragonite sand?  The live Fiji sand is very expensive.  I'm not sure if this is because it is live, or for some other reason.  I would prefer to use some dry sand and allow it to go live via the rock which I add.  Is there a different sand which can be added that would work well?  Can a very fine grain oolite sand (sugar grain size) do well as a simple shallow sand bed?
<Using dry sand is fine. Ask the LFS or a fellow hobbyist to give or sell a cup of there sand to get some of the critters that live in the sand and not rock. I would go with a little bigger than sugar grain size. There are many different dry sands on the market today to choose from. Go bigger than sugar size but smaller than crushed coral. It is really a personal preference. They all will work fine. MikeH>

To Have or to Have Not?--Substrate That Is. (12/28/2003)
Hello WWM <Steve Allen tonight>
I have read several articles on WWM on  the use of substrate in a reef system and still not certain which way to turn <there's always some dilemma>  --- I am setting up a reef tank from a previous FOWLR tank. It is a 75 gallon tank with a protein skimmer and two over the back filters rated for 125 gallon tanks. <Have you considered a sump with refugium?>  My live rock is full of coralline and based on my last reef tank I plan on getting plenty more to aid in nitrification.  With what I described would you recommend a substrate or not to use one at all <I don't' personally like bare-bottomed tanks for purely aesthetic reasons. If you don't want a DSB, then 1" of substrate would be sufficient. If you want the benefits of DSB, then 4-6". Some species of fish need a DSB for burrowing and some (certain Wrasses) need to bury themselves at night. I'd suggest you read more about the issues on WWM or the WetWebFotos forum. Bob & Anthony's Reef Invertebrates book has an excellent chapter on this issue.>  --- also would you run carbon or Poly Filters in this system. <Opinions vary. It is good to use these at least periodically. Do search WWM.> I will be using ozonized/distilled water for top off.  My ultimate objectives
with this system as I think it is for most is healthy organisms and as little headaches with brown diatoms and red slime algae as possible. <Keep the nutrients down.> Thanks in advance <you're welcome.>

BARE BOTTOM REEF?
Hey WWM, <IanB on call tonight>
A question about substrates for marine tanks.  I would prefer to have no substrate to eliminate the greatest amount of trapped particulate matter as possible,<Bad idea> yet am not sure about the negative impacts on marine life.<do read http://www.wetwebmedia.com/deepsandbeds.htm>
<http://www.wetwebmedia.com/marine/setup/filtration/biological/biofiltr.htm>
I understand the question is still contestable, but considering I wish to keep anemones, polyps, Amphiprion ocellaris and tube worms, is it advisable to go with the "bare bottom" approach,<definitely NO> or will a light scattering of aragonite sand really improve the hospitality factor of the tank to its inmates ???<again read through http://www.wetwebmedia.com/deepsandbeds.htm>
Thank you in advance for your time
Andrew Hough <your welcome, IanB>

Substrate
Hi Crew!!!
I have been reading through all your articles and FAQs on substrates and am still a little confused as to which one would suit my budding system. I have a 650l (180 gallon) with around 90kgs (200lbs?) of live rock, wet/dry sump and venturi skimmer under tank (+lots of powerheads for circulation). I plan on stocking the tank with a Volitans lionfish, snowflake moray, blue/regal tang and maybe an angle down the track (I plan on adding them in that order, a couple of months between each of course). My LFS recommends that I go with a very thin layer of crushed coral for the substrate but I've heard mixed reports on this. I'm not to keen for a DSB because of availability and cost but will go ahead if necessary (without the DSB will the live rock be enough natural filtration?)
<Yes, should be fine.>
I was thinking of a thin 1/2 layer of sand or the CC for aesthetic value? thanks for your thoughts and recommendations.
<Hi Joel, Don here. All sounds good to me. The crushed coral will need a bit more maintenance though. Hope this helps.>
Joel  -  Australia

Sand Bottom
How important is a sand / gravel bottom? Details please.
<A sand bed can be a great assistance in providing a stable, biologically sound system. Live sand should be utilized in a "deep sand bed", three inches or greater for best results. Deep sand beds help process nitrates and essentially act as a "living filter", which will greatly benefit many systems. Do research on the wetwebmedia.com site for much, much more info. on construction and use of deep sand beds>
I'm curious as I want to set up a small reef tank, using live rock, but don't want to have to move the rock to vacuum the bottom. Can I leave the tank with no sand?
What if I have the sand and don't vacuum it when I do the water changes? Any and all help would be appreciated. Sincerely,
Craig
<Well, Craig, you certainly can run a tank with no sand bed (the "Berlin" method embraces this philosophy), but I think that you'll enjoy greater stability in a system with a sand bed. Quite frankly, it is really not necessary to vacuum a deep sand bed, save for the top 1/2 inch, if you'd like, as it can seriously disrupt the biological processes that you are trying to cultivate. The use of purposeful animals, such as brittle stars, can help maintain the top layer of sand. Have fun researching and constructing your sand bed- your reef will love you for it! Regards, Scott F.>

Sand Bottom (Pt. II)
What type of sand would you recommend to set this up?
Can I use sand from my local Ventura beach (just north of San Diego)?
<I live near the coast myself, and  have contemplated using the local sand at various times, but decided not to. I think that there is too much risk of possible pollution, potentially toxic materials, etc. Also, with the state's coastlines facing erosion, I don't think it's an environmentally sound practice. Much better to use the bagged Aragonitic materials offered for sale to hobbyists for just this purpose, or perhaps even the famous "Southdown" play sand, if you can find it.>
>Will a DSB be beneficial in a 180G FO tank that already has sump, commercial Biowheel, Berlin protein skimmer, Ocean Clear filter, & UV sterilizer?
<I have ran very successful large FOWLR systems with deep sand beds. With good maintenance and attention to feeding and water quality, you can achieve very significant nitrate reduction using a DSB. Definitively worth looking into, IMO. Have fun with this! Regards,  Scott F.>

Changing Substrate
Hey Crew, hope things are well for all.
<Fabulous. Life is good!!>
I've spent the last few weeks planning to change a friend of mine's 29g tank from crushed coral over to a deep sand bed and wanted to run my ideas by you guys for whoever would like to toss their opinion on it. He is looking for something with less maintenance believe it or not he had paid for service on this small tank....I told him I'd take it over for just the cost of supplies...I thus decided to change it over to a 5" deep sand bed.  I figured now was great time to do so because the tank only has one inhabitant anyway, a tomato clownfish (and a few misc. snails).
<Yep! That will make things easier.>
Here's my plan:
---I'm going to drain a large portion of the tank into a large Rubbermaid container and place the live rock (only one very large piece) in it.  In a 10g I will place the clown and snails, including a small powerhead and heater.
<I'm agreeing so far...>
--If all the water doesn't fit from displacement, I will drain the rest into buckets. I will also have about 25-30% new water, premixed, in case of accidents---daydreaming, bad aim, butterfingers, etc..
<So far so good...>
--I'm gonna remove the crushed coral to a separate container and add the DSB.  I will then start to refill the tank with the bulk saved in the large container (I like to use plastic wrap to keep the sandbed surface disturbance to a minimum, has worked like a charm on other tanks).  
<I think I'm following you on this last point. I like to add the live rock to the tank first and then put the sand in to anchor the live rock. Then add water by placing a bowl or similar item into the tank on top of the new sand and pour the water directly into this bowl. After the water gets to a certain height, the bowl will no longer matter.>
I'll place the crushed coral in nylon or filter bags and place as many as possible in the tank to help seed the sandbed and help hopefully save the tank from having a major cycle.
<Sounds like a winner to me! Very well thought out. I have one suggestion...I am assuming that the DSB is new sand not live sand. In order to keep the sand from clouding the tank, wash the sand and let it soak in water two or three days. Then pour off all of the water and add the wet sand to the tank. You should probably use fresh salt water for the soak. It's no messier than adding it dry and you will avoid the dust storm. The dust cloud produced will only last a few hours at the most. If the DSB will be made of live sand there's no reason to do this.>  
--Finally, I plan to top off with any needed extra water, ensure parameters, and introduce the livestock back into the aquarium followed hopefully by a "happy ever after" moment.
<Hey-hey-hey! Sounds like a workable plan. Naturally you'll want to test the water for a few days but I really don't think the tank will cycle. Add new stock slooooooowly.>
Thanks for taking the time to read and critique, Ryan A.
<The pleasure was all mine. I'm glad to see you've taken the time to think this through. Experienced aquarists know that's the best way to avoid unexpected problems/complications. Good luck! David.>

Bare Bottoms and Live Rock!
Good Morning Bob--
<Scott F. here today!>
I am going to setup a 110-gallon acrylic corals only tank and thinking to  go with live rock only without any sand at the bottom - is this advisable? I already have 150 lbs. live cured rock waiting to put in the new tank.
Please advise. Many thanks in advance for your help. Michael
<Well, Michael- I have seen numerous systems operating with just live rock and no substrate. This was a major part of the "Berlin System" that arose in the eighties. Some people feel that the bare bottom enables you to siphon accumulations of detritus, making maintenance easier. On the other hand, many hobbyists who have run bare bottomed tanks have noted that maintaining alkalinity and pH levels is somewhat trickier, and this may be due in part to the lack of buffering that a substrate, such as aragonite, or even crushed coral offers. Personally, I feel that most hobbyists will be better off running a deep sand bed (of at least 4 inches) in their reef systems. Deep sand beds have proven to be highly effective at processing nitrate. There are some hobbyists who have run bare-bottomed aquariums with remote sandbeds in a sump, so as to get the best of both worlds. Do a little more reading on the topic of substrates and deep sand beds on the wetwebmedia.com site. You'll get a better understanding of the dynamics of sand in closed systems, and maybe you'll reconsider employing a sand bed. Good luck!>

Bare bottom vs. sand
Hey guys how are you doing?
I really don't want to sound like very one else that writes you, but WWM is probably one of the best websites on the net.  I won't even mention how addictive it is.
<I know what you mean, but it is the only healthy addiction I have.>
Anyway my question is regarding substrate in a reef tank.  Every local store that I look at recommends running bare bottom.  Their argument is that it will be more successful that way and it's easier to clean up.
<I don't know about more successful, but it would be easier to keep clean.>
Personally I really don't like the way it looks.  I would really like to know how much of maintenance will it require to have sand?
<not much, siphon it every once in a while.>
Also should I just stick with live sand or will it make no difference if I mix it with regular substrate?
<Not sure what is considered regular, but if you want sand I would stick with sand, if you want crushed coral, go with crushed coral.  Any substrate will eventually become live, starting with live sand is just a jumpstart for the biofiltration.>
What is your opinion on this?
<If you are going to go with sand use either less than 1in, or more than 4in.  And check out these FAQs on DSBs -Gage
http://www.wetwebmedia.com/dsbfaqs.htm >
Thanks you very much for your time
Pavel S

- Re: FOWLR Setup -
Hi Jason,
<Good evening...>
Thanks for speedy reply.  I just pulled this off my LFS website.  Can you comment on the suitability of shell grit at all?? <Is one of the main components of crushed coral and the like - all calcareous [containing calcium] materials.>
However, it is highly recommended to use a carbonate based substrate in marine aquaria, as this helps keep the pH stable. Marble is the most readily available option. Coral sand is also a good substrate, but it can no longer be imported into Australia so is difficult to get hold of. Shell grit can also be used, but you should ensure it is very clean. <I'm not a geologist, so I can't comment on the calcium content of marble, but I'd be very dubious about the solubility of the stuff. Calcium-based sands and crushed coral readily break down over time via natural processes in a marine system, supplying trace amounts of calcium. I'd bet that the same can't be said of marble.>
Thanks mate
Glen
<Cheers, J -- >

Substrate for FOWLR
I plan on starting a 150 gal FOWLR and would like to know what the best substrate might be.  there will be a dogface puffer and a clown trigger.  no plans for any other fish.  I'm not sure if I should put a thin layer of something down or a DSB.  if I go with DSB I already have the sand, just not sure if there would be any downfalls to it.
thanks
Jesse
<Mornin Jesse, it is really up to you, with big messy fish I would go with a thin layer of substrate that is easy to vacuum and keep clean, a DSB may become overwhelmed by these fish and their eating habits.  I like sand over the more coarse substrates because it is easier to keep clean.  If nitrates are a problem  maybe add a fishless DSB to the sump?  Maybe more LR? Take a browse through our DSB FAQs for some inspiration. Best Regards, Gage
http://www.wetwebmedia.com/dsbfaqs.htm >

DSB & BBT - 05/06/05
Hi Helpful Guru(s),
<Greetings>
With your help, I have claimed some success with my fish keeping for the past year & you people are the "gold" in our hobby. Thanks!!
<Thanks for the kind words.>
There has been a debate among my reefer friends on DSB (deep sand bed) vs. BBT (bare bottom tank). The DSB has been blamed as nutrient sink & BBT is the new & better way of doing it, if you are into SPS. With better skimmer technology, there are claims that one should do away with the DSB & just do BBT.
<If the DSB is working for you, why would you do this? Doesn't it make more sense to enjoy/reap the benefits of both?>
With BBT, you can blow the power heads any way you like & not be afraid of creating a sand storm etc...
<Won't argue that...>
What is your view on this issue?
<I like/prefer the DSB myself. Both can/do work, But it comes down to proper husbandry and proper application of the chosen methodology. I'll grant you that a DSB may become problematic, but ANY methodology will end in disappointment if you don't bother to research and apply it properly.>
I understand that DSB helps mainly in Nitrate Reduction. Right?
<A primary consideration, yes, but other benefits to be had as well.>
Even with a powerful skimmer only without DSB, can one get zero nitrate?
<One can get zero nitrate without a skimmer OR a DSB. It becomes a matter of adjusting stocking levels, feeding, water changes, manual detritus removal, etc.>
Or, the reason that BBT works in SPS tank since minimum feeding is required & hence minimum NO3 generated?
<Faulty logic/information my friend. Feeding and water flow rate above lighting in my opinion (and others here) for success with SPS and indeed all type reef tanks. The idea is to find and correctly apply a methodology where you DON'T have to starve your tank.>
I have a DSB tank housing SPS. Thinking of upgrading to bigger tank. How do I move the existing sand in DSB to the new tank so that all my bio filtration is intact & I need not go through the cycle of new tank?
<So, you want your cake and eat it too eh? <G>.  You must understand, the sand bed is made up of layers of micro- and macro-organisms. The organisms develop and function, indeed survive at differing depths within the sand bed. It's not reasonable in my opinion to expect to move a sand bed without experiencing some mortality of these organisms.>
If I move the sand just like that, I am disturbing it & may experience nutrient leach & toxic tank, right?
<You may, yes, maybe.... But your biggest hazard is a brief infusion of nutrients to feed nuisance algae, the so called "toxic tank" is more myth than reality. In my experience, any "toxic gas pockets" that are released exit the water column very rapidly, facilitated by good/proper water flow, with virtually no effect on the tank inhabitants.>
Does it look like my only viable way is to cycle a new tank with new DSB until it is completely cycled (i.e. 2-3 months minimum); then I can move my live rocks & my SPS over to the new tank?
<Not at all. You will have mortalities within the sand bed as stated previously, but not everything will die, thus providing a "kick start" to the cycle process. You will need to monitor water parameters to be sure, but I believe it's reasonable to expect the relocated sand bed to cycle within a couple weeks or less. You might even reduce that time by using a portion of the sand to infuse life in to a new sand bed if you like. Consider the fact that you will be also adding cured/mature live rock to the system.>
Gee, now you can understand why I am tempted to go bare bottom tank, no such problem in future; just move live rocks & live stocks. May I have your honest view on this matter. I would appreciate it.
<Have tried to do so. Relocating a sand bed is an arduous task. I would recommend seeding a new sand bed with a sizeable portion of the old bed, move your rock and livestock, along with most of the "old" water to the new tank, and go back to enjoying the hobby my friend.>
Thanks in advance.
<Regards, Eric R.>

- DSB or BBT -
Hi Helpful Guru(s),
With your help, I have claimed some success with my fish keeping for the past year & you people are the "gold" in our hobby. Thanks!!
There has been a debate among my reefer friends on DSB (deep sand bed) vs. BBT (bare bottom tank). The DSB has been blamed as nutrient sink & BBT is the new & better way of doin it, if you are into SPS. 
<Nothing new about bare bottomed tanks.> 
With better skimmer technology, there are claims that one should do away the DSB & just do BBT. 
<Not sure what the skimmer would have to do with this.> 
With BBT, you can blow the power heads any way you like & not afraid of creating a sand storm etc... What is your view on this issue? 
<Both have their uses, although it's my observation that fish definitely don't like bare bottomed tanks - or at least, reflective glass - they get bugged out by their reflection underneath them. Obviously, this can be remedied by painting the bottom of the tank. Otherwise, I think it's six of one, half a dozen of the other and really personal preference. What I do think is that many folks who implement a DSB don't actually have one deep enough, so they blame their problems on the DSB, when in fact the problem was one of improper implementation.> 
I understand that DSB helps mainly in Nitrate Reduction. Right? 
<Correct.> 
Even with a powerful skimmer only without DSB, can one get zero nitrate? 
<Skimmers don't remove nitrates - they can remove compounds that may become nitrates, but they don't remove nitrates directly and shouldn't be figured into a nitrate reduction scheme.> 
Or, the reason that BBT works in SPS tank since minimum feeding is required & hence minimum NO 3 generated? <Hmm... I think you're putting anecdotes together here where no relation exists. You could feed a DSB tank just as minimally... you could over feed a bare bottom tank... these are husbandry issues, and not relevant to a discussion of which is better, DSB or BBT.>
I have a DSB tank housing SPS. thinking of upgrading to bigger tank. How do I move the existing sand in DSB to the new tank so that all my bio filtration is intact & I need not go through the cycle of new tank? 
<It's actually not all that easy - disruption of the sand bed will cause your system to recycle - it may not take months, but for certain your tank won't be in the same shape on day one, and if you try to move everything at once, you will lose some livestock.> 
If I move the sand just like that, I am disturbing it & may experience nutrient leach & toxic tank, right? 
<Correct.> 
Does it look like my only viable way is to cycle a new tank with new DSB until it is completely cycled (i.e. 2-3 months minimum); then I can move my live rocks & my SPSs over to the new tank? 
<You could move some of your live rock ahead of time - would speed the cycle.> 
Gee, now you can understand why I am tempted to go bare bottom tank, no such problem in future; just move live rocks & live stocks. May I have your honest view on this matter?
<You have it - there is nothing wrong with either method, and one is not better than the other. They both have their advantages and disadvantages. If you decide to go with a deep sand bed, it needs to be deep - at least six inches. I've been running a 200g sump for almost a year now with 12" sand bed and don't have any problems with it being a nutrient sink. The sand is well populated with a variety of fauna which keeps things clean and healthy.> 
I would appreciate it. thanks in advance.
<Cheers, J -- > 

I am setting up a 110 gal. reef tank
My question has to do with substrates. Local fish stores recommend not using any substrate. They say that every tank they know of has problems within 2 to 3 years of set-up.
they claim it is easier to keep the tank clean and avoid problems. I would like your opinion of which substrate to use (if any) and how to prevent long term problems. Thanks for any help you can give. Tom Z
>>
I'm actually a BIG fan of using substrates in almost every type of set-up... maybe with the glaring exception of most culture systems... For looks, psychological benefits to livestock, buffering pH, adding alkalinity and biominerals... 
The arguments of cleanliness for excluding substrates are weak IMO, as I also advocate routine maintenance that includes gravel vacuuming in conjunction with partial water changes.
My choices in marine substrates include all the more soluble calcium carbonate based materials, Aragonitic grades, crushed corals, collected beach rubble sold under various names. The better grades are small (unless your biotope, livestock call for something else), and uniform in size and shape (spherical is best, to avoid packing, challenging)... of a few inches depth.
Some of the alluded to "problems" with old/er substrates can be avoided, in addition to the vacuuming mentioned, by adding, changing some of the substrate (the older it gets, the smoother, and less soluble, thus benefiting the tank less as time goes by). About ten percent after the first year, and about the same every half year after that will prevent any problems originating from a marine substrate. 
Bob Fenner

Marine Substrate
Hello, Mr. Fenner
<Howdy>
Is it important to have sand, crush coral, etc: on the bottom of the tank.
<IMO... yes... many more benefits than real or potential downsides>
I just changed tanks and did not use the crush coral that I had because I didn't want to stress the fish with the dirty water, but I did keep all the existing water. The tank is running properly now for 2 weeks without any substrate on the bottom. I would like to add live sand , but how do I do that with all the water and filters and everything running fine. I have a 55 gal with a wetdry and at least 65 lbs of live rock).
<My comments on these issues is posted on the www.WetWebMedia.com site under "Marine Substrates" and associated FAQs files... Yes to cleaning up your old substrate and gingerly scooping, siphoning... it back on to the bottom of the system... Lower the water level, clean up (yes, with fresh/tapwater the old substrate, and use a plastic "Tupperware" container (don't get caught by significant other...) to dip in and pour near bottom... a little cloudiness, no problem... Or you can siphon it all back in... but this requires a bit of gear and ingenuity... pumping just water back up, and using a large diameter siphon to vent the gravel and water into place...>
Thank you for your time. Jason
<You're welcome. Bob Fenner>

Water Circulation & Sand
Hello Bob. I have a couple more questions for you regarding my 75 gallon reef tank. Right now I am starting out slow on the reef and just adding a few soft corals. My first question is on circulation. I read about these tanks and the many powerheads and pumps they carry. I understand that vigorous water movement is a must with live rock. 
<I would say a "plus", or "beneficial"... you should come out sometime and see where this rock is collected... >
I have 90lbs. of live rock and 75 lbs live sand. I have a MaxiJet 1200, a return pump from my sump which is slightly larger than the MaxiJet, and one other smaller powerhead. Do I have enough circulation? 
<Maybe... you could test for dissolved oxygen... and always add more...>
I read about these tanks with 4 Maxijets like the one I have. That seems like too much to me, and too many powerheads to look at in the tank, than fish.
<Can be hidden... and/or use small submersible pumps, a "dump tank"...>
Second is on my sand depth. I read about people who recommend a thin layer and people who recommend a deep layer. Is my 75 pounds good or should it be deeper?
<Too general a question... but my "all in one" statements on "Marine Substrates" can be read over on our site: www.WetWebMedia.com
Bob Fenner>

Setting up a new tank?
Hi Robert,
I have to tell you first off, thanks for all your help the site is great and you're the man.
<Suspect we are>
I'm getting ready to set up a new 125 gallon salt water tank. I have a 55 gallon that is doing great. The thing I'm confused about is this:
Filters and Substrate
I have been told by some that wet dry filters are a hassle, by others that canister filters don't work. So need less to say I'm confused. 
<Both can/do work... both have their pros, cons>
It really is not a money issue as it's more what will work best in the long run.
<Hmm, neither. Look to building, buying a sump... or modifying the wet-dry as such... w/o the provided media...>
At first I was thinking about running a wet dry filter, a protein skimmer, an ocean clear canister and a UV filter with a Little Giant
pump. Needless to say, what do you think?
<Sounds like the best of all the possible arrangements>
The system will contain soft corals and fish. Lighting for the tank is 4-55 watt power compacts.
2-10000k and 2-6700k 03 bulbs.
I will be using about 110-120 lbs of live Fiji rock.
As far as substrate my best dealer in town tells me don't use any its a hassle later on.
I'm leaning toward his advice, but I really like the way it looks in tanks.
<I use it... would use substrate for all the reasons stated on: http://wetwebmedia.com/marsubstr.htm>
Thank you for all your knowledge and help.
Tony Hughes
<Be chatting my curious friend. Bob Fenner>

Tank Bottom
Hi Bob it is me again
I was wondering if its is a good idea to change my substrate. I like the way the sand substrate looks but I am not too sure how easy it is to clean. What
are the pros and cons in having sand substrate. Currently I have Crush Coral I believe has small sea shells)
<Please read: http://wetwebmedia.com/marsubstr.htm
Bob Fenner>
Thanks, David Garcia

Dumping the substrate
Hi Bob it is me again. I recently removed my substrate from my tank and at the same time I did a water change. The reason I removed the substrate was that my water had a film on the surface. I would do water change after water change and skim the top. Nothing would get rid of this film. I added the Kent Calcium Buffer and stopped because of the film, but there was no change. Now since I removed all of the substrate my water has never been so clear. I just received the Eco System 40 last night and I installed it.
According to the Eco people you do not need substrate but you and I know it serves a vital purpose. My question is if I decide to put back the substrate what type of substrate should I use to prevent this film incident to happen again. I read the info. on your website but I would like to have your professional opinion.
<Hmm, the site IS my opinion, professional and otherwise... Crushed coral is about the number one winner for most types of systems... Time re-read the "Marine Substrates" section my friend. Bob Fenner>
Thanks, David S. Garcia