Dark Live Rock (DLR?) Filter?
 

I'm thinking for my next tank that I may go for more of a prop tank setup where I put all my Live Rock in a completely dark sump. The display will be quite shallow (12" water) and have only dead base rock. Of course the system would also have a monster skimmer, Ca Reactor, RDSB (> 12" deep), 20% 'fuge, etc.

Thoughts? Anyone have experience with a completely Dark Live Rock (DLR) filter? I assume it would have most of the benefits and support a lot of beneficial organisms.

I'm fascinated with the Tyree TriZonal Crytpic systems but don't have the balls to go there yet...

I have a pair of Fluvals loaded with rubble live rock--- they are almost wall to wall sponges in there I'm not sure if this is indeed better than anything, but I also have chaeto in the refuge part of the sump--- so I can't vouch for too much--- I do know it's loaded with critters

Do you worry at all that without denser rock with anerobic areas that it might become a nitrate factory? Or do you have a DSB?

There's no reason why LR in the dark should work any better than LR in the light. In theory at least, it would be slightly worse, though the difference would probably be insignificant.

I wouldn't expect it to be "better" than live rock in light -- except that you don't have to deal with nearly the density of pest issues (hydroids, bristle worms (which in and of themselves are fine until they start messing with your corals and clams), UFO turf algae (which a few of us have and no snail will eat), etc.) You'd also have a little more overhead in dealing with the display pieces (adding, moving, or removing) without disturbing the core biological filtration system.

It's called a "cryptic zone", as promoted by Steve Tyree . The concept is that sponges, tunicates, and other life forms that don't thrive in our highly lighted tanks can grow and purify the water.

Here's a link to his website, [url=http://www.dynamicecomorphology.com/publishmain.htm]DE Publishing[/URL]

A search for cryptic zone brings up a lot of information. I've read the book and tried it on a limited basis. As an addition to typical techniques it works imo. The number of pods and tubeworms in my marginal cryptic zone alone justifies it.

I've read Tyree's writing on the method and was thoroughly underwhelmed with it. There's not much good science behind it.

Can't disagree with you. His tanks were holding tanks for imported corals. There was a constant influx of new organisms that skewed his findings. As you may have noticed I used the term "promoted".

Doesn't negate my observation that a low flow area with minimal lighting appears to enhance the growth of organisms that aren't prevalent in the display tank.

Yup - read the cryptic zone stuff. I'm fascinated with the concept and want to give it a try. It just make intuitive sense to me. Thanks guys.

[quote]Doesn't negate my observation that a low flow area with minimal lighting appears to enhance the growth of organisms that aren't prevalent in the display tank.[/quote]
I certainly can't argue with that.

What I do take issue with though are his claims about the roles of sponges and tunicates that contradict the primary literature and common sense. Plus the way he tries to present it as real scientific work and misuses terminology really annoyed me, but that's a style issue more than content.

i guess i'd rather follow the thinking of someone who's done this all for years (rather successfully!) as opposed to someone who articulates the literature correctly and eloquently and hasn't really spent much time actually growing corals on their own.

I tried for a short term - few months, may be. As a sump with biomedia (LR) and skimmer for non-photosynthetic nano-tank. Less problems with flat worms and red cyano, and less shedding from the rock. Like it much better.

One thing to pay attention: I had the rock for a coupe of months in it's own heated, circulating container, no feeding or dirty water from the main tank, still significant level of phosphates and nitrates in its water. The thing to be done before - seems, it's called to cook the rock - keep in the dark with water changes and removing shed detritus.

yup - i think cooking the rock is key. but i've found that even if you do, the rock will eventually shed and such and this gets old in a bare bottom...

a darkend area will work great, when I redid my system I put in some of my live rock I had from my my old system & put into my make up( trash can) 55gal of RO salt water and with 2 power heads, covered it and left it for over 3 months running until I got my system up going again, put in new sand, dead rock, approx 200 # then mixed back in my old rock and my tank really never went through a cycle, I kept waiting but it never happened, so I just started adding corals like 3 weeks later and fish, coraline started growing within like 2 weeks, and sponges started reapearing and all the little feather duster worms reawakened, even some zoa's popped up from some of the rocks, go for it! you will be just fine, they need hardly any light or indirect light, just look at everyones sumps & fuges, with hardly no light, full of coraline and tunicats, like Tyree is doing, we just make things to complicated, it's just way to simple.

awesome - thanks for sharing your experience and for the encouragement too!

-tE

[QUOTE][i]<a href=showthread.php?s=&postid=11520003#post11520003 target=_blank>Originally posted</a> by tonyespinoza [/i]
[B]...even if you do, the rock will eventually shed... [/B][/QUOTE]
But significantly less :) You will lose coraline too.

For a months I'm using the artificial ceramic media - Seachem Matrix biomedia (Pond Matrix is bigger, DeNitrate - smaller) in canister filter and in the sump. No shedding, fine ceramic cylinders should do the same, unlike the coarse AquaClear power filters ceramic cylinders.

I'm keeping it as a biological filter in canister filter, and in sump - for denitrification (pile in low flow area).

i worry about media like that not having the density to support anaerobic activity and thereby serving as a "nitrate factory".

not worried if the dark rock does not have coralline.

i will have base rock in the main display that will develop coralline and also denitrifying bacteria. but the difference is that the concentration of organisms in the display will be skewed towards my SPS as opposed to the live rock organisms (which will predominately reside in the dark sump). there will also be a reverse daylight sump with rock (equivalent size to the dark sump) and a 24hr fuge too.

funny.

i just posted my thread on discussion:[url]http://archive.reefcentral.com/forums/showthread.php?s=&threadid=1286582[/url]

steve tyree write up:
[url]http://www.practicalfishkeeping.co.uk/pfk/pages/show_article.php?article_id=544[/url]

my (dark rock) cryptic zone 'filter':
[IMG]http://i2.photobucket.com/albums/y38/bergzy/IMG_0018edit.jpg[/IMG]


differences in my sps display? better coloration, better polyp extension, noticeable increased growth. there could be other factors as well, but so far, i have not noticed any detrimental effects...yet. is it too early to make a definitive judgment? yes. will there ever be a long enough time frame to satisfy reefers impossible need for justification? nope.

cool! i just subscribed!