Benthic and agitated filtration stages - your thoughts

[guserto4]

I am considering an 'atypical' filtration design and am curious about benthic zones and agitated zones in respect to live rock and quality / quantity of filtration. Is there anything to gain by focusing on one, the other, or both in a trough style filtration sump? I want to try and rely on ATS, a Xenia fug & LR (and GAC & GFO and a skimmer in place but operating as backup).

I'm working on dividing up an 82x20x14" 90g tank into two long troughs with a 20g Xenia refugium partitioned on one end that will take in one trough and turn out the other. Im planning on something like 1000gph flow or an average flow rate of 0.67" / 1 second within each trough. Potential exposure distance is 110-120", up to 3 minutes contact time. ATS will be fed from the DT prior to this tank. The skimmer, GAC & GFO will probably locate near the end of this process.

SO is there a benefit to an agitation zone or should I just let this lazy river move on through? Is LR rubble best, or should I try mud / sand, etc.?

 

[mattberrytr]

This also interests me

 

[guserto4]

I have read several long threads about benthic zones and their usefulness, I just haven't read much about incorporating them in a trough system- for that matter I haven't read much about trough filtration systems in general. Hoping someone will chime in with experience. Thanks!

 

[Subsea]

I would consider cryptic and benthic similiar in purpose with much opportunity for denitrification bacteria to process nitrate. It should also provide habitate for micro fauna and fana to also uptake nitrate as well as other nutrients. Filtration of this type is considered nutrient recycling by producing food for filter feeders. Considering your overall design, I see little need for GFO or protein skimmer. What are you keeping in your display tank?

What does an agitated zone mean to you? For filtration, I see little usefulness. For oxygen and carbon dioxide gas exchange I use surface skimmers and trickle bed filters. Water from display cascades into the sump.

What do you mean by trough filtration system? I have seen raceways used with Aptasia to process nutrients. The raceways were used for breeding Aptasia eating Nudibrances.
Patrick

 

[Raul-7]

IIRC, someone posted a journal article that says they don't reduce NO3/PO4.