LR or LS first?

[justinx]

I am putting both lr and ls in my tank, but when i set it up, what order should it go in. some say rock first for stability, others say sand first to keep as much rock off the sand. whats better and why? <img src="graemlins//confused.gif" border="0" alt="[confused]" />

 

[ed r]

I vote for sand first. You don't want to cover your rock, plus it will be a lot easier to put the sand in when you don't have to avoid all the rock. If you don't have major burrowing animals, (I'm not talking about the small sandbed critters.) your rocks when pushed 1/2-1" into the sand should be plenty stable. I used pieces of PVC pipe, with large slots cut into the sides, to support my rock at the surface of the sand. It works fine, but is probably not worth the effort for the small benefit you might get. One other possibility, (if you don't have the rock already sitting there waiting to go in) would be to put the sand in and wait for the tank to clear (could be a few days). Then put your rock in. If the rock closely follows the sand, you always have the suspended sand settling onto the rock (can you say turkey baster?). Much of that could be avoided if the sand had already settled. Plus it is a lot easier to arrange your rock when you can see through the water.

 

[nm reef]

I would set the DSB in place then build my rock up if it were my choice. Much easier to work with in my opinion.

 

[justinx]

Well, i am going to put the ls in first, and wait for it to settle so that i can see what i am doing, but what do i do about the stability of the structure of the rock. I DO plan on haveing at least on sand burrowing animal and i dont want it to knock things over. (all this is only being put in a 20H tank)
BTW, what do you suggest for a burrowing fish that will stay very small?

 

[byrself]

you can sit the rocks down in the sand enough to make them stable. if you are going with a dsb, and have a sand burrowing fish, then you might want to use a plenum to keep the bottom layer intact for nitrate reduction bacteria.
my goby is a sand sifter. i don't have a dsb. it will still bury itself in the sand sometimes. mine has gotten kinda big though. about 4 to 5 inches long. but it still fits nicely with my 20g long. on a 20 high, i wouldn't go with the diamond goby. mine likes to swim around alot too. maybe a smaller goby would be best, i think the yellow headed gobies are relatively small.

 

[justinx]

is a plenum really neccessary? i didnt really want to have to do it. I was told that a DSB w/o the plenum will do the trick. is this true, or am i being mislead?

 

[ed r]

Don't use the plenum. With a DSB you shouldn't need it. Plus with that small of tank, you don't want to waste another 1-2" inches. I would also be afraid that the burrowing fish could expose the plenum. That could cause a problem. People who are successful with plenums have them covered by layers of substrate and screen which is intended to keep the burrowing animals from reaching it. Here is a link to Dr. Shimek's site, specifically sand beds. I feel he is the best source of scientific knowledge regarding them. Good luck with the tank.
<a href="http://www.rshimek.com/reef/sediment.htm" target="_blank">http://www.rshimek.com/reef/sediment.htm</a>

 

[rick58]

I agree, I definately would not use a plenum with a DSB.

 

[justinx]

Once again, another question. But first off, thank goodness i dont need a plenum. It seems far too complicated and artificial for my tastes. Another question though. I have read about DSBs that get hydrogen pockest or that solidify. Is this really going to happen. I am using 30lbs of aragonite sand and am toping it off with some live stuff from a lfs. (about another 10 - 2 0 lbs, whatever will bring it up to about 4 inches or so.) Thank you everyone for you help. It is greatly appreciated. Joining this BB has probably saved me a lot of money, not to metntion numerous lives. (of corals/fish/inverts etc.)

 

[ed r]

Read Dr. Shimek's info on sand beds. The more you know, the better. If you have the sand populated with the appropriate creatures, and keep it that way, there is no reason to have problems with hydrogen sulfide or solidification. The creatures continuous turn the bed over at a safe rate that prevents both of those problems. Clearly if you stock your tank with animals that will eat or kill all of the infauna, you would have a less efficient sand bed.

 

[justinx]

I read the article, and it was of great help. I had been told by my lfs that i need sand sifting animals (gobies etc.) to keep things happy, but i had always wondered/thought that they would desroy the bacteria in it. Do fire fish or scooter blennies burrow in the sand? (those are two possibilites that i want to keep in my tank) Would they destroy my DSB?