Replace crushed coral with LS???

[SushiFan]

I talked to Mike at Paragon Aquatics, where I am going to buy some LR soon. He recommended that I replace my 3 inch bed of crushed coral with sand. He said remove it about a third at a time over a few days - then add a base of the Home Depot Southdown sand and top it off with an inch of real live sand. He said the inverts I have should be okay during this procedure (if I don't crush them! - temporary bucket is probably a good idea..)

He had said that crushed coral will eventually develop pockets of baddie chemistry in the void spaces, as well as
trap detritus. He strongly recommends a sand bed.

Tank is 55 gal, ammonia=nitrates=nitrites=0.
pH 8.1, SG 1.023 Tank is 4 months old

I only have inverts - including 4 lbs of live rock (test to see how I like it before I dump a bunch in) 3 very healthy cleaner shrimp etc.

Filtration: Bak Pak II skimmer and Emperor with bio wheels and mechanical filtration bags only (to catch the
detritus that I stir up - especially if I replace the substrate.)

I've read some threads on substrate and they lead me to believe that sand is better.

Any comments/suggestions??? I don't want my stuff to die now that I (sortof) know what I'm doing!

Thanks in advance!
SushiFan.

[KC4IXA]

I like sand bottoms.

The sand will also develop pockets of decay. The trick is you can introduce some helpers to manage that problem for you.

Goatfish, Sleeper Gobies, small sea cucumbers, Partner Gobies, Watchman Gobies, and even small Pistol Shrimp in large aquariums should be stocked to sift the sand and keep pockets of rotting detritus from developing.

Use fine sand (about like sugar crystals) so the gobies can sift it through their gills.

A sand bottom is desirable both from an aesthetic and (especially) functional point of view.

Paul

[SushiFan]

Thanks, Paul,

One thing you alluded to that I forgot to ask about - unless I'm mistaken, the critters that turn over sand (such as the ones you mentioned) can't turn over crushed coral. Correct? Maybe some critters (starfish, etc.) can mechanically stir it some, but those that ingest it certainly can't (sea cukes etc.) - another reason to go with sand...

Daniel

[reefcam]

Live sand is nice, but can be bad if you have an acrylic tank. Only for the reason that a sand particle can be trap between your cleaning pad and acrylic which in turns create small scratches that will be undesireable. Also if you have currents that reaches the gravel, sand will be easily blown around than gravel. I do see pockets of air between my gravel, but that's telling me that my bacteria bed is healthy.

Just something to think about. Oh, glass will scratch as well. Not as easy, but will also scratch.

[dsb1829]

The esthetics of the sandbed are great for the reef IMO. I have been adding sand to my reef off and on for about four months. It gives a white and clean look to the tank. You, at four months, shouldn't have any major loss of organisms in the substrate if you slowly swap over to sand. It will still trap detritus if you don't have sifters in the tank. I have heard good things about the mini brittle stars. I actually have a couple that hitched into my tank, but I never see them. Good luck with the tank!

[KC4IXA]

That is correct Daniel. They can't sift gravel very well, and there's even some sand out there that would be a bit much. Grains the size of sugar crystals are about right.

Reefcam makes good points about scratching an acrylic tank and strong currents blowing the substrate around. You have to plan circulation a little more carefully with sand, but it's not a major concern.

Paul

[Alice]

Yes; you should replace the crushed coral; iit can cause real problems down the road. The system that you described for pulling it and repalceing it sounds like a good one.

One thing I want to point out, however, is that there is a big difference between sand *sifters* and sand *stirrers*. If you're going to put in a live sand bed and want to build up a population of infauna, you don't want sifters like Diamond Gobies, Banded Gobies, or white burrowing starfish. They'll wipe out the critters you're trying to cultivate in your LSB. Not too mention that the Gobies will drop sand everywhere and bury your corals.

Stirrers like the tiny brittle stars, bristle worms, Nassarius snails, spaghetti worms, etc. are beneficial. I personally won't put cucumbers in my tank...I'm not wild about putting something in my tank that can kill my critters by puking it's guts out.

I have sand in my small acrylic tank; I haven't had any problems with scratching.

HTH,

~Alice

------------------
Reefkeeping is my life; I can't afford a hobby too!

[RWD]

I have to go with Alice on this one. You don't want your sand bed turned over or sifted through if you are going with a deep sand bed. This can have a negative effect. For more info check this out: http://sites.netscape.net/douglxyzzy/sand4.htm
Bob

------------------
Check out my new web page: http://bobsreefermadness.homestead.com/index.html

[Doug1]

The live sand you add should be a little bigger grain size that will help keep the oolitic sand from blowing all over. The bio-chem processes in a deep dand bed are very complex and fascinating. It will benefit from a large diverse population of sand bed infauna. I would suggest about #5 livesand over the sugar sized sand, spread thinly to cover as much area as possible. Add a detrivore kit from IPSF or Inland Aquatics, or better yet one from each. Trading sand cultures with other established aquariums is a good way to add diversity. Add about 50 nassarius snails to help with cleanup, ut once you get the sand bed in and add the live sand DO NOT MANUALLY STIR IT UP. There are a lot of bio chem processes at wotk here and stirring it up will upset the balance, kill infauna and release unprocessed toxins, not worth it. FWIW I need to move LSB from 55g into new 75 and am not looking forward to the process

------------------
Reef as if your life depended on it, yours might but the sea's does
Doug moderator TheReefTank

[SushiFan]

Thanks everybody!

I appreciate all the good advice. I'll continue to slowly remove the crushed coral and replace with sand - then get some sand critters.

Thanks again,

SushiFan

[Garee]

No better time to do it than now. I once did the same thing on a 29 with 40# of LR and tank full of corals.