[smidoid]

So detrivores eat fish poo... so what do they poo in return? Who eats detrivore poo? Lower level detrivores, perhaps?

When I kept freshwater fish, poo was a bane - we had to constantly "vacuum" the stuff off the gravel and eventually had to remove and boil the whole lot because the UGF inlet snapped off... but that's another story.

If I understand correctly, in a properly balanced reef, most of the poo is scoffed by detrivores thus reducing the problem to a minium.

But which ones? Is it best to seed them from an LFS or a mate's display? Or try and get the right ones on the LR or do they just hitchhike in?

A lot of questions, sure, but this remains a fascinatingly broad subject!

[zhenya]

Marc,

In a perfect world, or a perfectly balanced aquarium, the final stages would be left to a bacterial populations.Assuming that that all the various poo's would be reduced to the stage where it would be available for the bacteria to consume.

The questions is broad, indeed, I guess a lot would depend on how exactly your system is set up. Do you have a DSB with proper infauna, do you have a bare bottom tank where all depends on physical removal of the proverbial poo?
If you read some of the articles by Dr.Shimek, you can probably tell that he advocates properly constructed deep sand beds, and aproppriately sized as well. The ultimate detritivore, in my opinion, is the various polychaete worms that inhabit live rock and sand beds. I will look up some articles for you on the dynamics of organics in reef aquariums, and consumers of it, too.

[smidoid]

I'm working through Dr Shimek's spinless columns (and others) right now Gene; The link you provided was invaluable.

I had already figured out that a DSB was the way to go for me (the sea, after all, has the largest one of all!). I purposely designed one in the fuge/sump when I was planning it. If I learned anything from this Reefland's moderators (yourself included) and keeping fresh, it pays dividends to plan, plan and plan! As to size, it's as big as the cabinet would allow - about 15% of the system capacity.

Since the whole system has only been "wet" for a week or two it's a bit early to tell what sort of infauna is inhabiting - if any. I really need to find some very fine-grain sand (my aragonite is sugar grain) to get the silty layer on.

This is something one can't really rush, but I'm a bit stuck because I'd like to get the DSB at least partly established before I add any fish! Catch 22!

[Floyd]

You could always get a live sand kit from some place like inland aquatics www.inlandaquatics.com They have the kit that you just put in you sand that has all the worms and other critters livesand needs.

[smidoid]

The gotcha for me Floyd is I live on the other side of the great salty pond! My LFS does sell a live sand kit but it's only aragonite pre-seeded with bacteria; hardly what you and I would call a detrivore kit.

I really need to find and join a local group - if there is one!

I do wonder how effective these claims are with bagged live sand - how, for example, are they keeping the bugs alive at low temp and over extended periods?

[zhenya]

Originally Posted by smidoid

The gotcha for me Floyd is I live on the other side of the great salty pond! My LFS does sell a live sand kit but it's only aragonite pre-seeded with bacteria; hardly what you and I would call a detrivore kit.

I really need to find and join a local group - if there is one!

I do wonder how effective these claims are with bagged live sand - how, for example, are they keeping the bugs alive at low temp and over extended periods?

Marc,

Given the limitations that you have due to the distance you live from any reasonable vendor that carries detritivore kits and such, perhaps joining local, or regional club is the way to go. You can always get a cup, or two, of live sand from a fellow reefer and seed yur refigium or display sand bed.
There is another vendor that sells this kits www.ipsf.com , however, I am not sure if they do ship to Europe or not. I am sure there has to be some other vendors that do this. Have you checked with your local reef discussion board?
You may also wish to read more about remote DSB's in Dr.Shimek's articles.
From my understanding, the secret to this is to make sure the stuff than needs to be processed by the infauna needs to be delivered to it( if it is remote).
Good luck with your searches...

[smidoid]

Thanks for the link, will check it out.

Transporting nutrients to the detrivores in the DSB. Ummm. Hadn't thought on that. I guess there is the manual root of vacuuming the cover sand and feeding whatever goes up the dump tube straight in to the drains.

My setup is designed for a fast laminar flow around the upper reaches of the tank with smaller currents cycling around the bottom. The sump drains skim the surface down to about 1". I don't think there's any "dead" water as such, but there's nothing to blow detritus back to the sump.

It's based on one in the LFS and works pretty well other than that. This would most likely explain the apparent absence of detrivores in their DSB (they very kindly (!) gave me a cup of LS with some dirty water to seed the bacterial beds. Probably only contained nitrosomonas though, the nitrospiras would be deeper, I'd guess.

More food for thought. (There's a pun in there, if you look!)

UPDATE: Found another Shimek article (from 1999) about DSBs where he suggests that we top up the detrivores every 12-18 months (well, that's what he does - and he's the PhD!). Still can't find the blighter on remote DSB sumps, will have to keep looking unless some kind soul happens across it.

Best

[My2heartboys]

Originally Posted by zhenya

Marc,

In a perfect world, or a perfectly balanced aquarium, the final stages would be left to a bacterial populations.Assuming that that all the various poo's would be reduced to the stage where it would be available for the bacteria to consume.

The questions is broad, indeed, I guess a lot would depend on how exactly your system is set up. Do you have a DSB with proper infauna, do you have a bare bottom tank where all depends on physical removal of the proverbial poo?
If you read some of the articles by Dr.Shimek, you can probably tell that he advocates properly constructed deep sand beds, and aproppriately sized as well. The ultimate detritivore, in my opinion, is the various polychaete worms that inhabit live rock and sand beds. I will look up some articles for you on the dynamics of organics in reef aquariums, and consumers of it, too.

Gene---does that include those darn bristle worms??? Right now I have several pretty good sized ones in my son's tank and when I feed---I try to go fishing for worms (yeah, that's what I do for fun on Friday nights ha ha). This last weekend hubby went to one of the LFSs to get a 6 line wrass---but came home with an arrow crab instead. LFS said it would do as well if not better a job on the worms as a 6 line. Yeah, right. So far it hasn't even touched any of the worms that I can see.

Here's one for the "Stupid Human Tricks" files. Last week about mid week, I was fishing for worms and tried to fish one out with my bare fingers. They don't call them bristle worms for nothing. Bad thing is that those bristles are the devil to find and pull out. Made for sore finger tips.

Anne

[zhenya]

Originally Posted by My2heartboys

Here's one for the "Stupid Human Tricks" files. Last week about mid week, I was fishing for worms and tried to fish one out with my bare fingers. They don't call them bristle worms for nothing. Bad thing is that those bristles are the devil to find and pull out. Made for sore finger tips.

Yikes!!! Sorry to hear you got nailed by those bristly things... It can be quite painful and yes, it is hard to remove them. I know that some people either soak fingers in vinegar or simply pee on their hand to help reduce pain and burning...

Gene---does that include those darn bristle worms???

Indeed! I would definately leave them alone and let them do their job- clean up the tank of uneaten food and help process it into a more menageable form for removal by skimmer or other filtration methods. The population of them sometimes explode but their numbers fall as food becomes scarse, most other populations of infauna is governed by availability of nutrition, at least in some part.
Perhaps you overfeeding your tank?
I have some large worms crawl around but not all that much during daylight periods, mostly at night and I can see them scavenging on the sand bed and rockwork. I had never seen them atack anything.
There are some predatory members of the so-called "bristle worms" but they are rare occurance and most of the time the worms we see are scavenging type polychaetes that could be safely added to the detritivore guild.
If you haven't read Dr.Shimek's series of articles I would strongly recommend doing so.
They could be found on his website in the "online articles" section.
http://www.ronshimek.com/Online%20Articles%201.htm

I really like this particular article, which I think relates to our discussion in this thread.
Waste Extraction, The Invertebrate Way

PS. Sorry, forgot to add article about the detritus and ways of dealing with it, with some additional links within.
The Infamous Detritivore

[smidoid]

Those are two pieces that are definitely worth mulling over - even if Dr Ron sometimes forgets that we're not all PhDs! I didn't even make college for pete's sake! ;-)

Gene: still can't find that Shimek piece on remote refugiums... a head's up would be great if you have the time!

[zhenya]

Originally Posted by smidoid

Those are two pieces that are definitely worth mulling over - even if Dr Ron sometimes forgets that we're not all PhDs! I didn't even make college for pete's sake! ;-)

Gene: still can't find that Shimek piece on remote refugiums... a head's up would be great if you have the time!

Marc, I can't recall with certainty if I read about remote DSB's( not refugiums becouse most refugiums are remote) in an article or in one of many discussions on his old forum "Ask Dr.Ron". It does not exist anymore but Dr.Shimek is hosting another forum here
You can ask his opinion on remote DSB's there, if you wish. IIRC, basically, he suggested that it is doable but the size of the bed must be as large, or larger, than display. Plus, the stuff that needs processing must be delivered to the sand bed and infauna within that sand bed. Otherwise the populations of critters will starve and be decimated. In my personal opinion, why go through all that if sand bed could be had right there on the spot( meaning display tank) ,within "short distance" so to speak.

[smidoid]

Wow! That's a lot to think about.

The snaggette with the remote DSB is that the poo gets held in suspension and then dumped in the fuge with its lower overall flow rate. Some writers consider that this can overwhelm the critters in there with predictable results. However, this is preferable to it dumping on the SSB (shallow bed) in the display tank and it can easily be siphoned off before it gets too much. Given the small size of my display a DSB would look rather out of place, I suspect so I'm a bit stuck with what I got!

UPDATE: Shimek has a small piece on that forum where he says that the remote DSB has to be at least the same area as the tank it's filtering. (I can't do that since the cabinet simply isn't big enough). Dr. Ron also says:

I have no idea what Anthony considers as a "RDSB," but I don't recommend remote sand beds at all. A refuge tank with a DSB in it, again set up with the appropriate sediments and animals will function as a biological filter for the refuge tank. It will not function as such for the display tank.

That seems a little harsh. Presumably the detrivores will have trouble - over or underfed - but surely the anaerobic bacteria will take up residence in the lower parts of the DSB and act as a nitrate reduction factory: rather like Dr Jaubert's plenum... or did I get that wrong!?

[zhenya]

Originally Posted by smidoid

That seems a little harsh. Presumably the detrivores will have trouble - over or underfed - but surely the anaerobic bacteria will take up residence in the lower parts of the DSB and act as a nitrate reduction factory: rather like Dr Jaubert's plenum... or did I get that wrong!?

Marc, I don't think it is harsh at all. It is true what he says, I think. Having trouble with nutrition(being underfed) means certain death for the critters and without them in the bed it becomes a nutrient sink, and a time bomb.
I agree with you that given the size of your tank you pobably will be better off with a different aproach than DSB. The denitrifying bacteria will be present in your tank in the rock, your other filter surfaces and tank walls..etc, etc. The trick would be to remove larger waste before it has a chance to decompose but you can mitigate this with increase flow and turnover in the tank to pump it out and let skimmer remove it. Isn't that berlin's method principle idea?
There is a lot more to it than that, of course, and I think Dr.Shimek explains all of that in his original article "Dear Mudder...".

[smidoid]

Umm... a time bomb, eh. Yes that's possible and I hadn't considered that.

My skimmer "lives" in the fuge (probably the best place for it all things considered) and yes, that's my interpretation of the Berlin method too. LR + skimming.

Actually, it makes me think that Shimek has an implied excellent point. A remote fuge should be at least as big and preferrably a LOT bigger than the tank it's filtering for. What struck me on the way to school (I do a lot of thinking when I'm on my way somewhere) is that you could have a remote fuge only a few inches deep (say 5"-6") but with a surface area of 1.5x to 2x the size of the display tank. With a deep bed and very shallow water flowing over it, this would provide excellent gas exchange.

I'll have to think more on my own design otherwise it really could become a ticking time bomb...

[zhenya]

Marc,

I hope you gave this article a good read over already. It should really explain how sand bed really works, in nature and how it should work in aquaria, too.

[smidoid]

No mate. Missed that one. Thinking cap on now!