Newbie ?? To plenum or not to plenum?

[414driver]

In the short amount of time I've been researching how to put together my first tank....I'm reading and getting conflicting theories on the use of tank bottom plenums.

 

What say you experienced folks?????? This will be a 48x18x25h..100gal.(scratch)

[undrtkr_00]

Like many things reef, you will get a lot of conflicting opinions, and sometimes they are all right! Most people here don't use plenums. Quite a few do use deep sand beds and large pieces of live rock for denitrification. Woody at Seahorse was a plenum proponent, you could ask him directly about his perspective. (503)-283-4788.

[wanareef]

Deep sand bed or shallow sand bed in the display and a deep one in the fuge.

 

 

my .02 - inflation = - .00

[andy]

I've never seen a Tank of the Month level tank with a plenum. IMO, they're an interesting footnote in the hobby, to be mentioned in the same breath as trickle filters, bioballs, algae scrubbers, mangroves as nutrient export, etc.

 

Do they work? Maybe. Is there a better way to accomplish those things that they may work at? Certainly. Again, IMO, I'd seriously question the judgment of anyone who insists they are good way to go. I'd also ask that person to show me their plenum-based tanks.

[tanktop74]

I did not run a plenum in my first tank, always had low level nitrites.

 

I decided to go with a plenum in my new 150 gal tank and have had undetectable nitrites from day one, and I overfeed!

 

I don't see the harm in it, and if you have a glass tank it even helps protect the bottom of the tank from the rock.

 

And yes I would call Woody or stop by seahorse. He will give good advice, pros and cons and if you decide on it will only charge you $10 for it.

 

Just my 2 cents.

 

Beth

[WAVES]

plenum = crazy IMO. the system is flawed it WILL crash, its just a matter of when.

 

no major author or known "expert" I can think of (even Schmenk sp?) is an advocate.

 

its 1980's mischief.

[pledosophy]

Spelling is Shimek .

 

Bob Goeman also spoke of it highly in his book "Live sand Secrets".

 

In my readings it seemed to me that the system could work for a certain amount of time but the specifications on setting up the system around the plenum greatly limit what you can keep and how you aquascape the system. Also if something goes wrong with the screen (say sand sifting worm, or snail) you have to tear apart the system to fix the screen. If the plate shifts to much it can release a lot of bad bacteria's and stored nutrients. The life span of the plenum can expire as well, so if not maintained (by tearing the tank apart) it can lead to a tank crash.

 

There are much easier ways to filter a tank for nitrates that are available for us today.

 

JMO

[grassi]

Spelling is Shimek .

There are much easier ways to filter a tank for nitrates that are available for us today.

 

+1... I'm a cheato supporter :-)

[WAVES]

Spelling is Shimek .

 

Bob Goeman also spoke of it highly in his book "Live sand Secrets".

 

In my readings it seemed to me that the system could work for a certain amount of time but the specifications on setting up the system around the plenum greatly limit what you can keep and how you aquascape the system. Also if something goes wrong with the screen (say sand sifting worm, or snail) you have to tear apart the system to fix the screen. If the plate shifts to much it can release a lot of bad bacteria's and stored nutrients. The life span of the plenum can expire as well, so if not maintained (by tearing the tank apart) it can lead to a tank crash.

 

There are much easier ways to filter a tank for nitrates that are available for us today.

 

JMO

 

I agree,, except for the part about busting my nuts for spelling. Anyone that knows me knows I can hardly spell my own name.

 

My point exactly. it WILL crash,, its just a matter of when.

 

Shot of vodka a day keeps the nitrates away!

[Emerald525]

Those are some pretty good arguments. Do you have any specific articles regarding this information so I can read up on this. You are definitely talking me out of plenums.

[acrylics]

There was a good article a few years ago by Rob Toonen called "Are Plenums Obsolete"

His emphasis being on deep sand beds IIRC

IMO to say they are "destined to fail" is a bit of a stretch but they are by no means necessary nor the best method. Plenty of folks have had good success using plenums through the years.

 

James

[Emerald525]

Thanks I will check out the article. Thanks for the more "balanced" opinon.

[pledosophy]

Those are some pretty good arguments. Do you have any specific articles regarding this information so I can read up on this. You are definitely talking me out of plenums.

 

Goeman's book is probably the best reading material on the subject IMO.

[andy]

Here's something: http://www.advancedaquarist.com/2005/6/aafeature#social

[undrtkr_00]

Thanks for the link, Andy, that's good stuff.

[414driver]

So...opinions are divided!!! As always!! How many of you who have personally used a plenum have had one crash.....or have you just read about? Not trying to be confrontational....just wanting to know how "first hand" your advice is!!!!

[Emerald525]

I have known others to use a plenum. I have not ever heard of a system "crashing" because of a plenum. As you can see there are many opinions but not a lot of hard evidence. I did review the article by Rob Toonen and the findings are interesting:

"Our experiment shows no evidence for any of the espoused benefits of a plenum. Instead our results suggest that any benefits seen are a direct consequence of the presence of the sediments themselves rather than the void space beneath it.

 

Overall death rates were roughly twice as high in aquaria with shallow sediments as in deep sediment treatments. The highest overall death rates were seen in aquaria with shallow coarse sediments over a plenum, and the lowest death rates occurred in aquaria with a sandbed composed of deep coarse sediments."

 

From what I gathered from this, is a plenum is not useful so why bother getting it? It seems like the compositon and depth of the sand made a difference but the biggest difference was simply the bioload particularly with the death of an animal. In my tank where certain people like to overstock and overfeed (whistle) , we are more likely to have higher nitrate levels.

[reefnjunkie]

In my tank where certain people like to overstock and overfeed (whistle) , we are more likely to have higher nitrate levels.

 

There are other ways of keeping NO3 down. I like to look at things in a way that "if" it could happen how would that affect/effect things.

With all the other ways to handle NO3 reduction, and a slight chance it can cause a tank to crash if any of the things mentioned happen-Its not worth the risk-

I too was going to do a Phlegm (ok Plenum), and after a few weeks of reading-I did not find anything that said "yep that's the smart way to go". My Nano I had when I got back into this hobby had one which is why I wanted to read about them-had not heard about them and I think it is because not many do it that way anymore-things have "advanced"

I did not find enough pros that outweighed the cons-

 

Like I said there are plenty of other ways to keep NO3 down-If I could do a fuge I would-hopefully on the next tank, since I will have MORE room

 

And if you decide to do the vodka dosing-read read and read.

 

I had a terrible experience and as such am not an advocate-It works for many, but like the plenum, IF it does not go as planned -stuff dies.

 

As frequently you are finding-Not black and white-WAY to many variables to have "solid" answers

[reefnjunkie]

So...opinions are divided!!! As always!! How many of you who have personally used a plenum have had one crash.....or have you just read about? Not trying to be confrontational....just wanting to know how "first hand" your advice is!!!!

 

I'm not so sure the opinions are divided based on people having their systems "crash" but achieving the same goal with "less" likely hood of disaster.

 

Plenty of people have had great success with certain practices-I've tried a few of those and had crap die-variables variables variables-

Never a perfect test group to get black and white

[Emerald525]

We have a refugium on the new tank which has really helped with the nitrate level and we also have a way better protein skimmer (Bubblemax). I have also noticed since we have gotton the calcium reactor and phosban reactor the water quality has improved and we have to do less water changes.

Interestingly we have less of an algae problem. Is this because of the phosban reactor or is it simply because the new tank has been up for almost 3 months and is done with the cycling process?

[MadReefer]

It's the refugium. Time will also help. My tank is at about 6 months old and I'm seeing less and less algae on my glass.

[tanktop74]

In my tank where certain people like to overstock and overfeed (whistle) , we are more likely to have higher nitrate levels.

 

Geeeee, would that be me?!?!?!

 

So I like my fish and like to watch them eat!

[andy]

Nothing wrong with that, I like fat fish and fish poop is GREAT coral food :-) Just manage the nitrates and be happy

[JManrow]

plenum = crazy IMO. the system is flawed it WILL crash, its just a matter of when.

 

no major author or known "expert" I can think of (even Schmenk sp?) is an advocate.

 

its 1980's mischief.

 

When Dr. Jean Jaubert of the Monaco Aquarium described his plenum system back in the 90's, many hobbyists including myself, felt they had to try this method. I was not impressed after it was set up a year. There are just too many factors involved for the system to work successfully, and you are taking a risk having a large stagnant anaerobic area under your substrate.

 

On one of his Portland visits, I had the opportunity to ask Dr. Shimek his opinion of plenum systems. He told me of the three reef systems he had at home, the only one that ever crashed had a plenum. Ron described how as he was sitting in his living room one evening, noticed a dark cloud of hydrogen sulfide "erupting" from the substrate in the tank, and how fish immediately died as they swam into it! This was enough to convince me to tear down my system the next day!