Deep Sand Beds

[jwburleson97]

I've read that deep sand bed (at least 3 inches) help eliminate nitrates...is that accurate? When I went to the LFS to buy that much aragonite for a 55 gal they looked at me like I was nuts. He showed me all of his reef tanks (which are gorgeous!) and none of them had DSB. He sold me 40# of aragonite, which is between 1/2 to 1 inch..is that going to be ok or should I add more?

 

[lando]

The debate on DSB is still out. Do not confuse this with using LS as a substrate choice. When compared to CC, LS is lower maintanace and does not trap detritus like CC. LS does not "remove" NO3 per say, however, it does not produce NO3 like a CC substrate does. In Theory, A true DSB needs to be at least 6in deep with little to no sifting in order to provide an anaerobic situation for effective NO3 removal. The down side is that they can also trap pockets of toxic gas that, when disturbed, can foul tank water. In most cases, a LS bed of 2-3in, with 1.58-2lbs/gal of LR, good skimming and regular PWC are all that are needed to keep NO3 at a low level.

 

[jwburleson97]

So maybe I need to add another 40# bag of aragonite. I do have 70# of live rock which will eventually seed the sand...hopefully this will keep down NO3. Thanks for your help!

 

[roka64]

I agree with Lando. I have about 2-3 inches in my 55 and about 4-5 inches in my 125. I have found when you add the sand, if you stir it after the water, this will remove most of the gas pockest. I used a PVC to stir and stir and stir.
Regular PWCs, light feeding will help to reduce nitrAtes. There are other things, like purigen, macro algaes and a few other things.

 

[lando]

Keeping low NO3 levels cannot be attributed to just one thing. There are many things you can do to stack the odds in your favor, no one thing will be all that effective...
1. Proper amount of biofiltration (LS and LR, sump or fuge).
2. Aggressive skimming.
3. Regular PWC using a good quality source water free of NO3 (RO/DI water is best).
4. Light feedings using a high quality food with good preparation of frozen foods.
5. Light stocking. Having too heavy of a bioload is a common cause of high NO3.

Overall good practice is your best friend in this area.

 

[tecwzrd]

4. Light feedings using a high quality food with good preparation of frozen foods.

IMO this tends to be the number one reason for excessive no3.

Fish always look like they are starving and begging because in the wild they are always looking for food and it's their nature to always seek food out.

People often confuse this with needing to feed them excessive amounts of food many times daily when in reality fish don't "know" when they are full and will gorge almost as much food as you put in the tank and the excess gets processed into no3.

Light feeding either once daily or even better every other day is a much healthier option for your fish and has even been proven to extend their life.

Read this post on feeding requirements of SW fish for more info.

 

[melosu58]

http://www.ronshimek.com/Deep Sand Beds.htm

Here is an article on DSB`s

 

[tecwzrd]

Couple of more links:

www.wetwebmedia.com
www.reefs.org

 

[jwburleson97]

www.wetwebmedia.com

This is where I read about DSB needing to be over 3" contributing to reduction of NO3. It also states that a sand bed below 1/2 will also contribute to reduction of NO3 and that anything in between can contribute to them. I was just wondering if anyone had any experience that went against that thinking.

 

[Kurt_Nelson]

I scoured the web when I was trying to figure out what depth I wanted my sand bed. To summarize... seemed like everything I read contradicted the other. Even within wetwebmedia, I found opinions that conflicted. Granted... there are always different opinions on things, but you can usually get a feel for what's valid and what's not. But DSBs... wow.

Anyway, I ended up with a hair over 3". Towards the front it's maybe a hair under, in the back probably closer to 4". After my cycle, I had maybe 5ppm nitrates in there. I did several big water changes, but could still detect a trace of nitrates. I then started doing my 10% weekly PWCs which I've continued to do for 6 months now. I have no detectable nitrates. What was there was either diluted enough that I can't read it, or was eliminated.

I've only got 1 fish in there so far, feed once daily with minimal leftovers, and have a beefy skimmer for the size of tank (Remora Pro in a 46g), so my nitrate levels shouldn't be bad to start with. I run GAC 24/7. I have no idea if my sand bed is contributing to my lack of nitrates. Probably not, but I have no way of telling. After a year or so, I might have a better opinion but it will be just that, an opinion.

So I guess I'll just weigh in with a "I've kinda got a DSB and it *could* be working" opinion. In the end, I'd say go with what looks best for your setup. For me, I put the rock work directly on the tank bottom and I filled up to where it looked "natural." Since then, I've rearranged some sand to expose a few more "caves" but for the most part have left the sand bed alone.

 

[jwburleson97]

I know what you mean...everything I read was a contradiction. I appreciate you sharing your experience...it has help me decide on what to do. Thanks!

 

[MT79]

Light feeding either once daily or even better every other day is a much healthier option for your fish and has even been proven to extend their life.

Do you have any links? I've read the exact opposite is true for most fish. Most recently in an article on feeding in the latest Aquarium Fish International Magazine.

 

[melosu58]

I dont have any links but I do have plenty experience. I have 4 of my fish that I started with 9 yrs ago. They are very colorful and great size. Several others over 6+ yrs. I`ll go with my experience over a magazine article any day. Every other day IMO is the best.

 

[Marc118]

There is a nice section in one of my books about DSB's, lots of info. References to Shimek, Borneman, and others. I could scan the pages if you all desire...not sure on the legality of that though.

Here are a few points.

It says that at DSB should be of aragonite oolitic sand, and is typically 6in or more deep. Borneman says that DSB's alone equals or exceeds the results achieved with more traditional methods of filtration, and that it offers the basis of removing skimmers on well established aquariums. Shimek says DSB's provide not only bio filtration but also food for many suspension feeders.

It also says that its not a simple matter of making side-by-side comparisons to measure results since the differences come from more that one variable ( as lando has brought up ).

It goes into much more detail about setup and maintenance, as well as a correct clean up crew for the sand, nutrient export, detritus accumulation, rock support, oxygen, changing sand, DSB in refugia, etc, etc, etc.

 

[melosu58]

I know there are different results from having a DSB and most of them good but I just dont like the look of them is the only reason I dont have one. Not trying to talk them down but just saying sometimes personal preference is a factor.

 

[MT79]

I dont have any links but I do have plenty experience

I've been keeping fish since I was 7 years old. That's about 20 years now, so my experience is in no way limited either. The article in aquarium fish mag is only the latest piece I've read. Feeding twice daily, or more for planktivores such as anthias, is the general consensus these days. Unless keeping predators such as eels, groupers, etc. With improvements in husbandry, filtration, and protein skimmers these days, nutrient export is not so much of an issue as it was say 10 years ago. Fish will absolutely benefit from a more natural feeding regiment. Having said that it is very important not to overfeed. For those starting out, be sure all food is eaten or removed, and start small. Also watch for algae outbreaks, and cut back feeding as required. From what I've been reading and IMO sparse feedings are a thing of the past.

jwburleson97, FWIW I use a shallow sand bed of about 3" w/ a protein skimmer, regular PWC's, and GAC 24/7, like Kurt . It's been up and running for over 2.5 years w/ no issues and good overall growth including SPS's. HTH

 

[melosu58]

no hard feelings. You have your opinion and I have mine.

 

[jwburleson97]

It says that at DSB should be of aragonite oolitic sand, and is typically 6in or more deep

What about aragonite special grade reef sand? Does it make a difference? I did move the sand from under the live rock.
Thank you for everyone's input!

 

[Ziggy953]

I've been following this and haven't said anything as yet. I spoke with a guy that has had tanks for over 20 years and he does not use DSBs because of the toxic gas release. I'll try and find the link for it but what he said was that after 2-3 years the gas that gets trapped in the sand bed will begin to leach out and CAN cause a tank to crash. The way to avoid this is to over the course of a year slowly replace the sand. I am with MT79 on this...my sand bed is 3-4" deep in both the main and my fuge.

 

[Marc118]

This is what the clean up crew section goes over, certain clean up crews are designed for DSB filtration that promote oxygen penetration and maintained porosity, not letting gas get trapped....

Not taking sides, just readin a book