Placing Live Rock On/In or Above 4-6" Sand Bed?

[DGB]

I have decided to set up a deep sand bed after reading some of Biogeek's posts and many others over the use of a plenum type design. I wanted to get some guidiance on how to place the live rock. I realize that the more surface expose of the live sand bed the better. Should I support with adequete pieces of cut PVC on end so that the live rock is hovering 0-1" above the sand bed? Or should I place the live rocck directly on top of the sand bed? Or place the live rock on the glass bottom and fill the sand around?
Thaks for any help.

[DougL]

DGB;
You have another vote to elevate it, for whatever its worth. Actually, support it at about the correct height and the sand will do
whatever it wants. so some of the rocks will end up covered. However, if the weight is supported by pedestals, it will work
out.

Hope this helps;

DougL




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http://sites.netscape.net/douglxyzzy

[Jeff B]

It's always seemed like a good idea to me to elevate the LR above the sand bed as a means of enhancing water circulation. One idea to consider is the use of Tonga branch rock as a base with the bulkier LR on top. I constructed my reef with this method 3 years ago and have had minimal problems. I do not have a plenum and my sand bed is about 2" deep. There is also a new product on the market that allows for the construction of a platform and shelves to raise the LR above the sand bed. It looks like eggcrate and Lego blocks. Check out their website at reeftimber.com.

[OhMatic]

I used ABS pipe to elevate the LR about a half inch above or even with the sand the circulation works well this way it looks like the LR is resting on the sand, I have more LS than I would if five inches of LR was burried in sand and the chance of a burrowing critty causing a rock slide is nonexistant

[Q-ball]

yep, another vote to elevate the rock off the sand. I used the method Jeff mentioned, I have a bunch of tonga rock, I used some as stilts resting on the bottom of the tank, then placed shelf rock on the "stilts" then stacked the rest of my rock on top. Very stable, and very good looking. I thought about using pvc as Ohmatic stated, but didn't want to be able to see it sticking up. Just my .02

Q

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wife: "What's it going to cost THIS time?"
;)

[Larry M]

I've tried it both ways. In my 65 I placed pvc on end directly on the glass, then put a layer of eggcrate on top (holes drilled in the sides of the pvc). the whole thing comes out to be about 1/2" below the top of my sandbed.
In my 40 I set the rock right on the sandbed.

So far, both seem to be working fine.

I don't buy the argument that sand-digging critters will topple a pile of rock stacked on the sandbed. For one, if you listen to conventional wisdom about sandbed critters there wouldn't be anything that large or destructive in your reef anyway.
Also, once the rock knits together and settles into the bed a little, no amount of digging by critters like worms is going to move the rock, IMO.
As for nasties building up under rockwork piled on the sand, I have never seen proof of that either.
JMO

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Larry M

My Personal Site, Northern Reef (http://www.homestead.com/larry_reef/index.html)

[REEFPOWER]

Any other members have replies? I too soon will be encountering this situation. Any suggestions, comments, or present situations are greatly appreciated.

Sorry for barging in on your topic DGB.

GiL

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Gillty@Aol.com

"God is Perfect, Man is Not. Man made Beer, God made Pot"

[RobertK]

I bought my LR from Harbor Aquatics and followed their recommendations for supporting the rocks as shown on their website (http://www.harboraquatics.com/setup/index.html). I cut lengths of 1-1/4" PVC pipe in lengths equal to or slightly longer than the desired depth of my sand bed. The pipes rest on the bottom of the tank. I used three of them to set each rock on, with a few 1" sections here and there for smaller pieces. It was kind of a hassle and took a while to get the bottom pieces stable, it involved trial and error in placing the PVC pieces until each piece of rock was stable, and if you want to move the rock a little you have to move all 3 pieces. However it was effective at creating open space around the base of the rockwork for water flow and the structure seems quite stable. Later on when I re-did my sandbed I switched to some sections of 4" ABS to set the larger pieces on and it seemed to work better than the tripod method. All of the pieces of pipe have lots of big holes drilled in them so that water and critters can move through. The other thing you need to know if you use this or a similar method is that some sections of pipe may be visible around the base of your rockwork. You will need lots of smaller pieces of LR to place around the bottom to conceal the pipes. I did this and you can't see any of the pipes. I don't know if this is the best way to do it but it worked for me and I am satisfied with the results.
Good luck,
Robert

[DwayneNelson]

I tried placing my LR on PVC stilts above the sand, but I have to tell you it was very difficult. You have to find pieces that will fit the locations of the stilts you choose. BTW, I used 2" PVC. I finally gave up and placed the LR on the sand. I did this about 5 months ago and have had no problems. I really can't see why you would want the LR floating above the sand. The harbor aquatics site mentions detritus, but I don't have any so that isn't an issue (for me). I have read about animals diggin and causing the LR to fall, but I can't see that happening either. I pushed the LR into the sand a little.

Dwayne