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Any member running a bare bottom tank?

The BB tank would serve as a display tank with a lot of flow the sand would be blowing around even once it matured to a safe point I have a 29 with a DSB & Plemed every time I go in the tank I have to turn off the filters because every thing gets blown around just buy having my arm or scrapper in the tank redirects the flow also this tank is about 2 years old even with a euro 5-3 on the tank it still had nitrate I put a 7 inch DSB no plem in a small tank and once cycled I put it on the a system nitrate 0. So in the next couple of weeks Im going to move everything over to the 75 and leave the DSB on the system and the break down the 29 and start that again later
 
I have atleast 30x turnover in my 20l and it doesn't effect the sand at all.
 
Not the best pic but here is the epoxy bottom. The sand looks just like regular southdown..which it is just has been glued...I can point a ph at the ground and never worry about sand blowing or debri coating. I up the amt. of lr to about 90 pounds between a 33 gallon and a 10 gallon fuge. As you can tell I do have a diatom problem. Some of the rock is new and some 3+ years in tank.
 
super cook said:
The BB tank would serve as a display tank with a lot of flow the sand would be blowing around even once it matured ... every time I go in the tank I have to turn off the filters because every thing gets blown around just buy having my arm or scrapper in the tank redirects the flow
Do you think that's too much flow? You're giving your fish quite the workout:) I don't mean to criticise, or even sound as such. I am just somewhat surprised by the large amount of flow.
super cook said:
...this tank is about 2 years old even with a euro 5-3 on the tank it still had nitrate
Did you try a refugium with macroalgae?
super cook said:
...I put a 7 inch DSB no plem
Skip the plenum on a DSB. I guess super high flow is one way to prevent detritus buildup on a bare bottom tank, but it coulds till find a corner to accumulate it. What about a shallow sand bed that would not be impacted by disturbance (no anaerobic zone)?

Matt:cool:
 
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The 29 was set up following the bullet proof reef tank plan by garf it has a mag 3 overflow and 2 mj1200 and 1 mj900 on the 3 walls of tank at varied hights they are on a red sea wave maker reef 3 so any thing from 1 to all three are on in a random cycle I got told that there is no such thing as to much flow by one of the speakers at the UMass meeting a while back so now that I have drilled my own tank and got my OM 4 way Im going to plumb it in through 4 holes at varied hights through the back of the tank and do it over the top too with the revolutions by OM as a closed loop on a Mag 36 and use a mag 9.5 as the over flow with the hight and plumming total will be about 45x flow Ive been planning this since last april and the idea of the bottom of the tanf covered with coarls has grown on me yes I have a small fuge but very young started it up to get ready for move to bigger tank.
 
Matt L. said:
Do you think that's too much flow? You're giving your fish quite the workout:) I don't mean to criticise, or even sound as such. I am just somewhat surprised by the large amount of flow.
Matt there are people running BB with 75x turnover (and want more). I am going for about 55-60x..
 
I sometimes run around tanked BB...does that count?
 
But seriously, is the intention of a BB to reduce detritus and lower nitrates?
FWIW, I had a probelm with nitrates way back in the day when I first started out. I would routinely vacuum out the detritus and make huge water changes to no avail. Finally I just cut back on my bioload (feedings for the most part) and added a 5 gal refugium. Nitrates dropped from about 50 to 0 in about 3 months. Since then, I've never had a problem. Currently my tank has 4" of a coarse sand/small gravel bed.
 
I think the main intent of a barebottom is:
#1 Not to have a built in "waste dump", IE an area that will collect waste
#2 To allow as much flow (MEGA-flow) without a sand storm
#3 To be able to "easily" vacuum out detritus & other junk
-but of course we all know how easy it is to vacuum around rock work-

I think the real "value" of the BB is the high flow rate you can achieve, and the fact you can blow the rocks clean

Having a refugium w/a sand bed woudl be the best of both worlds
My main tank has a 2-4" sand bed, the refuge has a 6-8" sand bed
 
I look as BB as a way to reduce detritus, since if I can see it ... I do something about it. Similar to my hardwood floors vs. carpet at home.

I look at the DSB as a way to reduce nitrate by the bacteria, and as a source of calcium (argonite).

I don't think it matters whether a DSB is in a refugium or the tank,... I am sure that plenty of "stuff" get's sucked down there to be removed by either the skimmer or broken down by the DSB or the culerpa in the refug.

I like the look of a sand bottom, but heard that ~ 2" of sand can be a source of nitrate(I need to go back and find where I read this) ... but then I 've seen tanks with 2" that look great. ... I just haven't been able to make it happen. I am guessing it has a lot to do with water flow, and other elements of the setup.

My experience:

I tried for about 2 years to get a plenum (reading Goemans books) working, but with a 20 (and at that time - no refug.) .... I always had a nitrate problem. I think it was because I never committed to the deeper bed ... ~ 3.5 inches .... since the tank was so small. ... when I pulled the sand out ... things were better... I concluded the sand bed was producing nitrate.

My present setup is still new ... ~ 4 months ...BB ... DSB in the refug. with lots of Caluerpa... Euro Reef with plenty of circulation in the tank .... went through a big hair algae bloom about a month ago ... it's all gone now, and looks better than any tank I 've had (this is #4) ... maybe it's the FSW changes.
 
Wow i was researching the price for starboards, the stuff is very expensive. Probably because the board is huge and shipping is costly.
 
I'd like to see that article about sand beds being a source of Nitrate.
If kicking up a sandstorm is an issue, has anyone considered a layer of coarse sand, then medium gravel on top?
 
having a course layer is a no no. The waste gets stuck and builds up.
 
Marko ... I think the sand beds as a source of nitrates is in one of the Goeman books,... I am on the road right now, but get back this weekend ... I 'll look it up. I may be misinterpeting something out of his plenum setup ( I havn't read them in a while).
 
Not sure what constitutes a coarse layer, so here's a photo of my sand bed. Lwt me know what you guys think. BTW, that's a dime in the picture.
 

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Hello Marko,

Dug through the library, and this is what I came up with ...

In Reef Secrets by Nilsen and Fossa there is a BB or sand bed overview ... 1 page. .. Nitrification (Ammonia... nitrate) takes place in the top level of the sand where oxygen is present.... where oxygen is low (bottom of a deep bed) ... denitrification takes place (Nitrate.... Nitrogen).

I more or less conclude from this that if oxygen is always present in the sand ... denitrification won't take place ... so the sand bed isn't producing nitrate, but it can't break it down either, so nitrate will build up.

Reef Secrets says 1" to 2" bed if always stirred ... no problem. It also says coarse sand is safer in deeper beds vs. fine sand, but never defines thick or fine.

In Goemans's Marine Algae Control Secrets he talks about water changes doing little, and "Nitrate flowing out of the rock and sandbed interiors" ... which I believe is more or less in the context ... if you don't have denitrificaiton going on ... you 've got a chronic problem.

Goeman leans towards 1mm to 2mm sand, but this is in the context of a plenum/jaubert system.

If you want to read about the chemistry going on in the sand bed ... I 'd rec. Live Sand Secrets by Goemans ... it's mostly on the Jaubert system ... It's also cheap ~ $7. My copy is a little dated ~ '98 and discusses adding a Jaubert system in series with an established tank, but never uses the term "Refugium". ... I think there is an updated version out there.
 
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