Plenum

Dave3112 · Jan 7, 2011

I am thinking of making a combo plenum/fuge for my system. I have about a 25g compartment in my sump used as a fuge right now. I have a couple of macros and some LR and I am trying to decide on adding a DSB in there and remembered reading about a plenum system on GARF a long time ago. I guess my questions are:

1) how many of you on here run them in your system?

2) would that small of a plenum benifit my system? (I have about 275 total water volume)

3) what are the pros and cons of such a system?

Thanks in advance!!

Dave

Wy Renegade · Jan 7, 2011

I've set up a small remote fuge with plenum on a 210;

If I were going to do it again, I would either do them as seperate containers or only do one. A fuge to be totally effective requires a relatively slow flow through rate (although several types of macro algae will grow well even with a high flow rate), while research on DSB indicates that they should have an extremely high flow rate across the surface to be effective. While this can be accomplished in a single container, it is more difficult and requires multiple pumps. Part of the issue with combining is that the algae will contribute a large amount of debris on its own to the DSB.

IMO, the more types of effective filtration that you can add to the system, the better the system is going to function. That said however, it also depends on what you have time to maintain.

Dave3112 · Jan 7, 2011

my sump is a 75 gallon tank with 3 sections. From left to right I have a skimmer section then a return section and finally a fuge section. Both the fuge and skimmer sections are fed from the display and both drain into the return section. I would estimate that I have about 300 GPM flowing through the fuge side at the moment. I can add a powerhead if needed. Why would you separate the fuge from the plenum? I can still grow macros in the plenum correct?

I have tried to research the plenum type filter on here and can't seem to find a lot of info. GARF has some but I want more than one source I guess.

Dave3112 · Jan 7, 2011

I guess I am thinking that a plenum and a DSB have the same concept but not the same structure is why I was wondering about the flow.

Wy Renegade · Jan 7, 2011

Dave3112 said:
my sump is a 75 gallon tank with 3 sections. From left to right I have a skimmer section then a return section and finally a fuge section. Both the fuge and skimmer sections are fed from the display and both drain into the return section. I would estimate that I have about 300 GPM flowing through the fuge side at the moment. I can add a powerhead if needed. Why would you separate the fuge from the plenum? I can still grow macros in the plenum correct?

I have tried to research the plenum type filter on here and can't seem to find a lot of info. GARF has some but I want more than one source I guess.

Generally most of the research I've found indicates that a properly set-up DSB with plenum is neither more or less effective than a properly set-up DSB without a plenum. I had a buddy do a DSB in the display of a 210gal tank - we did DSB w/ plenum on the left and right third and did the middle section without a plenum. He had more initial and longterm algae and cyano issues with the plenum area than the non plenum area. Personally, I always build my lowest level of the DSB with course substrate (I uses shells or CC gravel), cover with a screen mesh, and then layer my sand. Supposedly the bottom layer in the DSB should be slightly acidic, so that should add the breakdown of CC or shells into calcium and dKH to add the corals (or at least that is my logic).

The general issue with the combined DSB and fuge is simply the accumulation of debris from the algae on the sandbed. If you keep your algae well-groomed I personally think you should be able to nullify much of this and thus combining the two should be no big issue. Just my $.02 worth.