Stirring Sand Beds

lossman · #1 08/11/2007, 08:14 AM

I have heard both sides of the story on this one. Some will say you should stir your sand bed, some say don't because you'll kill stuff in it. Is there any studies or hard evidence supporting one side or the other? If you should stir, how often? Is there such a thing as too often?

Almost seems that since we started stirring our sand bed more regulary, nitrates went up a bit. We also lost some corals on our rock.

Thanks

Gary Majchrzak · #2 08/11/2007, 08:21 AM

deep sand beds shouldn't be stirred.
shallow sandbeds probably should be stirred.
if barebottom you catch a break on this maintenance as long as water flow is good along the bottom

(A DSB is a deep sand bed of 4" depth or greater)

Criminal#58369 · #3 08/11/2007, 08:59 AM

If you stir it up a lot it will cause organic matter to be released causing your Niterates to rise and possibly an ammonia spike.

Sk8r · #4 08/11/2007, 09:40 AM

It can be lethal, not to the bed so much as the whole tank.

The way to clean them is to get critters such as the fighting conch and nassarius snails, plus [if you're expert] a tigertail cucumber, etc.

The deal is, if YOU do it, you don't eat the waste, which gets loose in the water and robs the water of oxygen, plus contains various nasty chemicals that are safe down under the sand, NOT so when up in the water.

The critters eat the nasty stuff and their moving through the sand [like the sandworms in Dune] is so specific to a tiny area they never bother the chemistry, except to consume part of the problem and convert it in their stomachs to much better stuff.

HTH.

ihopss · #5 08/11/2007, 10:19 AM

I would not stir the sandbed 1" or 4",buy critters to do the job.If you do ,you need to do a large water change after.

ikaros · #6 08/11/2007, 10:28 AM

i have ~100 red legs in my tank and they do a great job along w/the turbos

WaterKeeper · #7 08/11/2007, 10:34 AM

Remember that the bed's primary function is to develop anaerobic zones where nitrate will be stripped of oxygen and converted to nitrogen gas. Stirring the bed upsets the balance and and oxygenates the anaerobic zones. This defeats the prime purpose of having a DSB in the first place. If you have a good population of worms, mini-stars and other bed dwellers they will doing the stirring for you without upsetting its function.

Oh, and

Hi Ikaros

To Reef Central

yakfishin · #8 08/11/2007, 10:52 AM

I have a shallow sand bed- averages about 1" deep although water movement and my maroon clown causes it to get deeper in some areas and almost non-existent in others. I think with a shallow sandbed stirring is ok- and perhaps beneficial. I will occasionally push the sand back in areas to even it up here and there. But I wouldn't say that I'm actually stirring, more like a gentle raking. Since the sandbed isn't deep enough to create anaerobic zones such as waterkeeper described, I think moving the sand bed a bit here and there helps to keep it from getting too overloaded with nutrients. I don't see any detriment to my bug population, in fact, just last night, I was amazed at the number of various pods I had darting across and around the sandbed. I have also have a sand sifter starfish and he seems to be fat and healthy- but I have a vary large sandbed for him to sift around.

Ronan021 · #9 08/11/2007, 11:20 AM

this is defintely a (((((very confusing))))) issue

i have the book 'reef invertebrates' by calfo/fenner...
and they recommend stirring the top 1-2" of the dsb occasionally

which makes sense to me...
(for what its worth)... even though it might wipe out some portion of the good critters... as far as i see it... this is a good thing allowing for a 'new' colony to come along and repopulate the area and essentially start over new... (potentially) making it stronger etc... but i am new to the marine hobby and am no expert myself...

it seems like this approach is in the minority...
even by the people who advocate dsb approach

i have been hearing about dsb 'crashing'
at the lfs which the mgr advocates bare bottom (or 1-2"beds) tanks and is opposed to dsb...

i have a fw background (african cichlids)
and the dsb approach i can relate to based on my experience... but in the marine hobby there seems to be so much confusion about the dsb that i question its merits... although i do have a dsb in both my 125 main reef display and the 50 gal fuge (210gal system)... my nitrates have been zero (cant even remember the last time i measured any nitrates at all... prob more attributed to large colony of xenia though) but i have been battling high phosphates for several months.

regards

Sk8r · #10 08/11/2007, 11:31 AM

Those of us who apparently say 'don't touch it' are all saying 'don't touch it yourself'. Let the critters who specialize in that niche do it safely, as they do in nature. Add a fighting conch and you'll find him eating off the surface until there's a reason to go below: and then you may not see him for a month or more. He'll be down there doing his thing in the substrate, and the problem you'd have been hunting for in vain is being targeted and solved.

bigbubbacain · #11 08/11/2007, 11:37 AM

Quote:

Originally posted by Sk8r

The way to clean them is to get critters such as the fighting conch and nassarius snails, plus [if you're expert] a tigertail cucumber, etc.

HTH.

Are there any other critters that can be used in a FOWLR tank? Will any of the Starfish varieties work in a FOWLR tank? If not, what are some other options?

romunov · #12 08/11/2007, 04:55 PM

The sand bed needs to be stirred. Just not by you.
The issue isn't confusing if you have most (all?) the facts.
There is a mountain of evidence speaking in favor of no-stirring. The branch of biology that works with sediments is called benthology, and any scientist will tell you that the highest animal diversity is in a healthy non-disturbed (ever heard of dredging?) mud.