Question on plenum

[Volitan]

Hi all

Thinking of using a plenum system for my "new" tank. Read from this forum on plenum as follows:

"Before you dump a lot of gravel into your tank, thing about what you ultimately want to do. Fish produce waste, other creatures need to clean it. A primary waste product is nitrates which can accumulate high enough to "burn" the fins off fish. There are two basic ways to remove nitrates, bacteria and changing water. Bacteria are much more efficient and work 24 hours a day and grow naturally - free is good.

To have these bacteria present, we recommend using a PLENUM (plen-um). This is simply a water space under the gravel. We use 3-4" pieces of 1/2" PVC tubing lying sideways to support egg crate (the white, plastic, 1/2 by 1/2 square hole, fluorescent light diffuser) which we then cover with fiberglass window screen. Cover this with 2" to 3" of #1 aragonite (a-rag-go-nite) and Mother Nature will do the rest."

Anyone knows what is a fibreglass window screen? Can it be replaced with other stuff? It's meant to keep the sand from falling into the plenum area right? Appreciate any advice.

[mUAr_cHEe]

My guess is that it is just to keep the gravel from falling underneath.

From what I look at it, its same as DSB. easier to run a DSB? Definately, the below set up is an eyesore compared to seeing alot of sand.

My 2 Cents.

[May&Bruce]

a few of us reefers here are running tanks with plenum systems. If you do a google search on Jaubert plenum system, you will find lots of information on them.

[May&Bruce]

Anyone knows what is a fibreglass window screen?

I think they mean a woven plastic fibre fine mesh that stops coarse sand from falling through...

[Volitan]

My guess is that it is just to keep the gravel from falling underneath.

From what I look at it, its same as DSB. easier to run a DSB? Definately, the below set up is an eyesore compared to seeing alot of sand.

My 2 Cents.

I was hoping that plenum is more effective in denitrifying than the DSB. As for the eyesore, can either cover up or use eye drops lah.

[Volitan]

a few of us reefers here are running tanks with plenum systems. If you do a google search on Jaubert plenum system, you will find lots of information on them.

So I guess we can use anything that prevents sand from getting into the plenum area, but must have openings to allow water exchange between the sand and the plenum?

[cci[RR]us]

There is this article by R. Shimek that talks about DSB and plenum: http://72.14.203.104/search?q=cache:VMoJfp...lient=firefox-a

Somehow his original website is gone, this one is a cached copy.

[Volitan]

Thanks for the info. I gather that the link focus more on DSB compared to plenum. I have read in some websites that different sizes of sands are used for the plenum. Is it ok if I use only grade 0 throughout the setup?

[mUAr_cHEe]

Thanks for the info. I gather that the link focus more on DSB compared to plenum. I have read in some websites that different sizes of sands are used for the plenum. Is it ok if I use only grade 0 throughout the setup?

Grade 0 is abit too fine.

Others did advise me on using a blend of grade 1 and 2.

Grade 1 bottom layer, grade 2 top layer.

But if you ask me, I can't bloody tell any difference.

[Volitan]

Grade 0 is abit too fine.

Others did advise me on using a blend of grade 1 and 2.

Grade 1 bottom layer, grade 2 top layer.

But if you ask me, I can't bloody tell any difference.

I understand there may be some issues for using sand that is too coarse, but it does not really matter if grade 0, 1 or 2 sand is being used in a plenum right? I prefer grade 0 for aesthetic reasons, and I already have it in my present tank, so can also save a few bucks.