Guys, please clear this up for me...

[bonermeister]

I have been under the impression that with a live sandbed (DSB) you don't want to buy any fish or other organisms that feed on the worms by sifting the sand. Because the organisms that crawl through the sandbed turn it over to prevent "deadspots" or areas of detritus and food decay. Well, I was just at a rather reputable website that said in the profile these exact words about the Royal Gramma:
"Royal Grammas make great additions for reef tanks, staying small, not bothering invertebrates, and keeping deviant live rock critters, like benthic crustaceans and worms in population check."
Can they somehow discern between "good" benthic critters and "bad" benthic critters and only eat the bad ones? Or does the author not know that the small crustaceans and worms in the sandbed are good for the sandbed and health of your tank?

 

[bang guy]

I've never seen a Gramma eat anything that wasn't in the water column.

 

[fishkiller]

hmm, good one.... I think it may be saying that you can have the royal gramma if you don't mind losing some of them. As far as telling the good ones from the bad ones-Idunno. Darwin would say that the bigger, smarter one
s stay near the bottom away from predatory threat and reproduce enough to send all the young one's to the top to feed and feed the gramma. If you had quite a few grammas then you would more than likely experience a death rate of the crustaceans and worms that would out-weigh the birth rate which would eventually lead to nasty DSB, and dead spots. Keeping a population in check does not mean wiping out a population. But hey, this is only my opinion.

 

[fishkiller]

PS- Yeah, then again. Ive never heard of Royal Grammas eating anything in the sand.,

 

[bonermeister]

Thanks Bang Guy. Is it true though that you do want to avoid anything that would eat the organisms that turnover your sandbed for you? I have read that it is often difficult to maintain a decent population in an aquarium in the first place with no predators. Most people often need to "re-seed" their sandbed every year or two with detrivore kits and stuff.

 

[bonermeister]

Thanks for your post too, Fish Killer.
You must've posted the exact same time I was replying to Bang Guy.

 

[bang guy]

Originally posted by Bonermeister
Thanks Bang Guy. Is it true though that you do want to avoid anything that would eat the organisms that turnover your sandbed for you?
This is very true. In the wild reef these predators are scarce compared to our aquariums. You would be hard pressed to find sand sifters within 10 - 20 feet of each other. Sticking one in a 4 or 6 by 2 foot aquarium is just begging for a dead sand bed. My refugium has an 8 by 8 foot DSB and I have no doubt it could be cleaned out by a single sand sifting star.

 

[bonermeister]

Thanks Guy, I don't know much, but I want to make sure what I do know is correct before I start my reef!