Help Needed On Plenum design

[Bear]

Hi, I want to design a plenum for my 75g and would appreciate any info or help.

Thanks
Jerry

 

[Reef55]

My advice is not to use a plenum. Just use a normal sand bed. There was a talk at one of our meetings this year about it too, and the same was said then by the speaker. I used a plenum once upon a time, and would not go back to one ever.

 

[Bear]

Thanks Mark, But can you briefly explain why? I'm starting to read up on it and would appreciate the explanation.

Thanks


Jerry

 

[cobraz]

I was at the meeting in Framingham .... The speaker said that the Plenium actually caused less death than an just a sand bed - other then that 1" vs 4" sand there was no difference. So for more stability and survival rate a Plenium is the way to go...

Use electrical egg crate (Home depot) cut it 2" from all sides of inside of tank.
Place plastic pipe or bio media to raise the bottom of the light diffuser 1" above bottom of tank. Also use egg crate on all sides to create a 4 sided box with no bottom. Wrap with nylon window screen ( no metal screen ) cable tie together and place at bottom of tank. Fill tank with 6" water or so.. the trick is place a heavy weight ove plenium to keep it down and then place live sand over it 1 cm to 2 cm size (Carib Sea has special reef sand for pleniums). You want a total height of 3.5" to 4" from bottom of tank ( Not plenium) you can also put the first 2.5" to 3" in then add a layer of window screen then pour the last 1" over it - this way if you have any gobies they will not disturb the plenium.

PM me if you need help - been running several Pleniums for 20+ years.

 

[super cook]

Go to garf.org look at the bullet proof reef item

 

[maurod]

Yes, the speaker did state that plenum vs non plenum had less deaths, but the data was statisically insiginificant (and he pretty much admitted this)



M.

 

[dz6t]

Had less death of what? coral? fish? reefers?

 

[Lurchin]

I believe DSBs work just as well as Plenums w/out the additional hardware. Rob Toonen actually did a scientific experiment. Here's a link: http://www.advancedaquarist.com/2005/6/aafeature

 

[Reef55]

I wouldn't go back because it performs the same as a deep sand bed, with the possibility of failure. I actually had airline tubing ran from under the plenum to the outside of the tank, so I could remove small amounts of water from down there. Let me tell you that is some of the most foul nasty water I've ever had to smell. If something digs in your sand down to that level and that water mixes with your normal tank water, good luck to your tank inhabitants.

So, does it work? Yes.
Does it work statistically better than just a DSP? No.
Does it have a possible catastrophic tank causing feature? Yes.

So for me, when I took down that tank, I went with a deep sand bed for my next tank. Now I don't worry about something getting down there.

 

[Matt L.]

I recommend avoiding a plenum

In my professional opinion, there really is no need to use a plenum. They serve no point from a microbiological standpoint, and in my personal opinion, they are an outdated technology harkening back to UGFs.

Regardless of how much substrate you use, from zero on up to several inches, the health of your reef is determined by your reekeeping, and the diligent reefkeeper shoud always experience zero loss.

Matt

 

[Matt L.]

I do not believe a plenum can denitrify

I wouldn't go back because it performs the same as a deep sand bed, with the possibility of failure....

I actually do not see how a plenum would be able to maintain the anoxic conditions required to perform denitrification.

Matt

 

[daves-reef]

FWIW
I had originally planned on using a plenum but after a lot of research decided to go with just a DSB instead. There didn't seem to be any added benefit.

I would definiatly read the article that has already been mentioned. It was one of the factors I took into consideration.

"Orinally posted by Lurchin

I believe DSBs work just as well as Plenums w/out the additional hardware. Rob Toonen actually did a scientific experiment. Here's a link: http://www.advancedaquarist.com/2005/6/aafeature "

If you do decide to go with a Plenuim I would also recomend the http://www.garf.org web site. A lot of my system is based of the information I found there including the DIY rock. I just decided to go without a Plenum. So far I have had great sucess with my system. But of course only time will tell.

Dave

 

[Bear]

Well, being new to the club and to reefing, I can see that this forum is going to be of great use to me. Thanks to all of you who responded. My tank is full of water right now and 1" of sand (not live yet) and just letting things settle. So I'm going to read a bit more on both methods and think about all the info you guys gave and make my best discision based on that.

Thanks again guys for the info and if anyone else has some info that would be great!!

Jerry

 

[Jocko]

Yeah the difference in mortality rates presented in the study were not statistically significant. In fact the overriding theme from the whole thing was that none of the variations in substrate setup really makes much difference. This, of course, is great news because it explains why after all these years there's never been any agreement on what is best.

I find it rather counter productive to see plenum-advocates going so far as to imply that this the conclusion of the study was that plenums are better. If you want to do a plenum then go for it. But it is extra work and there is no data out there to prove it has an advantage over any other approach.

Bare bottom of course is a different story, but I assume we aren't going there. Every approach will have people with success and failure. Studies such as the one presented at the meeting are starting to show us that perhaps its not the sandbeds but the zillions of other variables in the equation that are the cause.

 

[delta]

The discusion at the meeting was simple. The depth and application of the sand didn't matter one bit, other than there seemed to be a corellation with deeper sand beds and lower death rates in fish.

So all hoopla over DSB vs SSB vs BB is "BS"

Always felt that way anyway I would say look at all your options consider all you can and pick what you feel best suits you.
I have seen people do things I would never do but in the end it works for them so its all good.

GL what ever you do. If you really want a plenum GARF.org is big on them you might look at their site.

 

[Matt L.]

So all hoopla over DSB vs SSB vs BB is "BS"

Proud SSB user for 4 years now -- I've never had a DSB.

Matt

 

[dz6t]

Plenum is another "wishful" thinking product.

Since there is no difference from SSB and DSB, the DSB bucket theory should be out also, right?

 

[go4broke44]

it seems that there will always be controversy. The speaker you guys are talking about said there is no difference in sandbeds, where as people like GARF and Anthony Calfo swear by things such as the plenum, DSB, and DSB bucket, all of which having success stories. I'm sure all three are very reputable sources, yet I guess it all boils down to how well you take care of your own tank.

 

[dz6t]

Anthony Calfo also said calcium reactor was not necessary for a tank less than 200 gallon. I think he is right.

 

[naturebatslast]

Also, Calfo was really hip on a remote DSB, I think less hip on the plenum.