Hmmm anyone want to talk about this one?? AGAIN

[wave98]

I was laughing at the guy wheeling wheel barrows full of manure across the border, because he was "burning the wheel barrows". Then I coudn't catch my breath for quite a while when he was caught because of the "smoke" ! ! ! ! !

> Barry

 

[Skimmy]

The "cwp" IS the "flushing toilet" ! Elsewise take out the carpet and the beds, and walk and sleep on glass ! ! !

> Barry

i know, that's what makes it so ironic that i can use the argument for a skimmer"flushing toilet" in a nano

 

[jeffkeith_us]

Kalkwasser might be a bit "old-school" still it's uniquely “revolutionary” when used in tantem with a Calcium reactor, however. Kalkwasserpowder is an excellent source of calcium, hydroxide ions to buffer alkalinity, has unmatched ability to encourage coralline algae growth, and it precipitates phosphates out of the water.
I say that with Kalkwasser (used in tandem with a calcium reactor) you should build your Deep Sand Bed without even a thought about "phosphate release."

 

[aquarookie]

Aargh! You guys are giving me a headache! I guess I am still too new to this to try and follow a thread in advanced discussion. And here I thought I would have the sandbed question settled once and for all in my mind!

 

[JoshF]

looking at this after a long while, but I wanted to add a different aspect of DSB's that might be getting overlooked.

I haven't read the specific article being referenced here, but have looked at a LOT of other articles over the last 6-7 years and ran a DSB tank for 3 years. I also ran a crushed coral tank for 2 years.

It appears that people are looking at the substrate as purely a mechanical filter. In both my DSB and the crushed coral bottom aquarium, the large amount of life in the substrate made the biggest difference to me. It was different life in each, but both had very complex, very active ecosystems going. It was the web of biological interactions beyond simple bacterial colonization that made both systems fairly effective. Everytime one organizm ate another, and nutrients were recycled, broken down and reprocessed, the efficiency of the system increased.

It's great to pull the waste out of a tank with a skimmer, and my next set-up will probably have a skimmer, but not one of the huge ones that are so popular. The other main action that the diverse ecosystem supported was food production for the rest of the aquarium. I NEVER had to feed my fish, and they never starved. This includes a psychodelic mandarin fish which was always fat and happy in my little 55 gallon. We don't know what many corals eat, and try to replicate it with blended foods, Cyclopeeze, and phytoalgae, but this only starts to approach the diverse production of foodstuffs from a DSB in particular. Especially at the smaller end of the food particle size spectrum.

Anyway, just reminding people of one of the main benefits of having substrate versus simply nutrient removal. Otherwise BB and skimmer would always win hands down. Of course, BB, skimmer, and a DSB or crushed coral refugium that's as big as the main tank would be a pretty nice, but fairly cumbersome way to go!

Josh

 

[MikeS]

Well, the study in the article in question focused primarily on livestock mortality vs. substrate depth, it really didn't dive into the complex issues of the biological workings of said substrates, nor did it address the "mechanical" aspect of them either. It was simply (and poorly engineered) an attempt to observe a cause and effect realtionship between substrate type, depth, and livestock mortality.

On the subject of biodiversity in a DSB, my own experience with having a DSB in my reef for 5 years was that microfauna diversity tapered off with time. This was probably due to many factors, like certain species outcompeteing others for resources and space, predation by other organisims in the tank, and a physical change in the DSB environment itself as it aged. Personally, I feel that it is difficult to maintain a good diversity of essential microfauna in a DSB over the long term without periodic reindroduction of new microfauna.

As for the mechanical aspect of a substrate...well, thats also a pretty complicated issue (it's been batted around a bit here at RF in a few threads ). So many factors will play into it...substrate depth, particle size, flow dynamics, impact of burrowing microfauna and larger livestock in the tank, amount of solid waste introduced into the substrate, ect, ect, ect.....

MikeS

 

[JoshF]

Oh... perhaps it's been said already, but even if done really really well, it would only provide one piece of evidence in a much larger puzzle. To try to derive a boolean yes/no answer on DSB versus bare bottom looking at mortality with depth seems like a gross over-simplification.

I do have to say that I probably won't do a DSB in the main tank again. I just want to crank too much water through. However, a DSB based refugium makes a lot of sense to me (as does a skimmer, don't get me wrong.)

I hear you on the biodiversity of macrofauna in the DSB. However, that does not take into account the microfauna production, larval release, bacterial colony release, etc, that act as foodstuffs. Even with periodic restocking, it still seems less expensive than buying dead foods to mix up as the only source. Probably a mix of all the above is the most effective, but who knows? That's why we bandy these ideas around. I do come from a lazy aquarist mindset, but also from a strong belief in a chaotic system producing really good benefits and stability. It's like the discussions of nano reef stability. There's just too many parameters to make the tiny systems as stable as large ones. Adding even more complexity and microhabitats to larger systems might make them even more stable, and yet more able to self-sustain. It makes sense to me anyway!

Well, the study in the article in question focused primarily on livestock mortality vs. substrate depth, it really didn't dive into the complex issues of the biological workings of said substrates, nor did it address the "mechanical" aspect of them either. ect.....

MikeS