Looking setup/filtration input

[sambo1]

For those that frequent both boards, I have also posted on RC. Thanks...

Hey everbody. I'm new here. Been reading for a month or so (everything I can find on reef sytems) and am looking for some input from those with real world experience..

My wife and I will be setting up a 225 gal tank during the next 6 months, or so. We hope to build a reef system with a few fish, and a wide variety of both hard and soft corals. It looks as if I will use a 55 gal tank for a refugium and a large Rubbermaid tub, or something for a sump. Twin 1.5 inch overflows will supply flow to the sump and refugium from the main tank. I have twin 1 inch returns for the tank. I thought I would have lower flow through the refugium and overflow this into the sump along with the additional overflow from the tank. I had hoped to cycle the flow through the two returns in order to change the water motion in the tank.

What do y'all think of my initial setup plans? Refugium big enough? Large tub good for sump? Should I light the sump and refugium at night to help control pH? How often to y'all change the flow patterns in your tanks? Hourly, daily, etc..??? Flow rate through fuge?

I am also trying to decide what type of filtration I will use. I will admit I am torn between a plenum system and a DSB sysytem. Every time I think I have it figured out, I get another opinion. EVERBODY has one!!! I have read extensively on this and many other site about the merits of each. The amount of work to build a plenum is not an issue. I have plenty of time. It seems most here use DSB. Is that true for larger tanks as well as smaller ones?

Could I put a plenum in the main tank, and a DSB in the sump and refugium and get the merits of both? Would this lead to additional bio-diversity since I have more varied grain size?

Advice on any of the above, as well as what I may have missed, is greatly appreciated. I figure the homework now, will save me, as well as my fish and corals, in the long run.

Thanks

 

[Len]

Hey Sambo,

Lots of great questions (and great attitude about doing your homework now) and I'm sure you'll get varied opinions. Here's mine:

A 55g is a sufficiently large refugium for a 225. The larger, the better, but 55 will do nicely. Rubbermaid containers are high value containers for sumps, but I personally prefer using an acrylic sump since they're more rigid, transparent, and durable.

As for DSB vs plenum, I'd personally go with DSB. I've had poor long-term success with plenum systems and have heard numerous bad accounts of such systems. Some recent anecdotal reports have suggested that DSBs "crash" over time as well, but I've had a DSB in my 120g for 10 years now without a hitch. If I had to pick between DSB and plenum, I will take a DSB 100 out of a 100 times.

A safe alternative is to use a more shallow sandbed in your display tank (primarily for aesthetics and a limited habitat) and utilize a DSB for your refugium only. That way, if you should encounter problems with the sandbed, you can disconnect the refugium easily and replace the DSB painlessly. If you're going this route, I'd go with as large a tank as you can fit for the refugium.

A plenum system won't add additional bio-diversity to a DSB. It's primarily purpose is a denitrifying bed which a DSB will do just as well (an opinion supported by the likes of Toonen).

For current, I recommend and use Sea Swirls to randomize/alternate my flow patterns on a continual basis. Two 1" Sea Swirls would serve your tank well. Tunze makes an awesome wave-making system called the Streams. With the controller, you can have variable oscillations, not your typical on/off operation found in wavemakers. You could also employ an actuating 3-way ball valve to automatically oscillate flow from one side to another from a single large return pump. While these circulation options aren't cheap, they all work very well and I recommend them all.

That's my two cents

 

[sambo1]

I also have heard "rumors" of DSB's crashing. That's why I'm looking for opinions on both systems from those with experience. My reading says that both can be very successful if executed properly.

My idea behind more diversity, came from an article I read on here that talked about sand particle size for DSB. The author gave grain size ranges and the number of organism that prefered each. He implied that a more varied grain size, while not optimum for any group of critters, would promote more diversity. I just took the idea and ran with it. Figured a DSB is grains from .05 up to around 1mm or so, for a plenum system 1 - 4 mm or so,therfore, having both would give me more diversity. Not exactly sound scientific method, but it appealed to the engineer in me!

As far as circ., I had thought that I would build two manifolds, one for each one inch return, and alternate flow through each. I also have three mj1200's that I thought I could pull water from around/behind/under/etc.. the live rock, to promote flow in "dead" zones.

 

[Len]

How did you plan on alternating the flow through the manifolds? Manually? An actuating ball valve could do it automatically on a regular, constant interval, but they are pricey. Look into the other circulation options I listed; they'll save you a lot of busywork and your tank will be better for it

Grain size is definitely significant in enhancing biodiversity and it's a good idea to mix a few different sizes into a DSB for this reason. You're right about the possible bio-diversity advantages of using both plenum and DSB. I previously thought plenums were roughly the same grain size as DSBs but referring back to my reading, I'm definitely mistaken. (I'm admittedly rusty on plenum systems since I have a bad impression of them over the last decade). It's your call. I've already stated my opinion on plenums The whole methodology is based on the success of Nice Public Aquarium in France, and those aquariums aren't even closed systems like our reef tanks.

 

[sambo1]

Thanks for the input.

I had thought that I would pursue several options to change the flow. Ball valve similar to what you described, or a seperate pump for each overflow/return. Seperate closed loop. Etc.... I can tell you this, it won't be manual! It's still up in the air at this point. Time, money, what I can build myself, and what I may find on the "bargain rack" in the future will all dictate design.

The more I read, the more I realize that the arguments for DSB vs. Plenum vs. other filtration systems has as much emotion in it as science. It reminds me of one of my other hobbies, wakeboarding. People will spend days in a forum arguing over who makes the best equipment, when only one in a thousand are good enough for equipment to make a difference!

I just finished an article by Sprung (?) on why a plenum system is good and then he states that DSB's have come into favor but he has no research on them as of yet. The article was a couple years old. In Advanced Aquarist, I believe. Same site had author #2, can't remeber his name, saying plenums suck, DSB's all the way. At least Sprung mentioned that they were a potentially good thing and kept an open mind. So many authors seem to be all my way or you're just dead WRONG! Of course, they may be right. Time will tell.

It does seem that the majority of reef keepers have moved to DSB's, however.

 

[Rainman]

ooooh. Bit of a DSB v. Plenum thread. ahaha!

I've personally got a plenum on my 35gal outfit. It's been running for about 3 1/2 months. So far, not too sure how well it's working (the nitrates seem to be stuck at about 10ppm). It probably just needs more time to get going. As for a crash. Surely if your levels kind-of creep up on you, one can take evasive action, like bypassing the plenum.

 

[sambo1]

This is one of those threads that could go on forever based on the past threads I have seen. I just was hoping to get some more specific answers to MY questions that were generated from reading previous threads and articles I had found. This idea of population type and density base on the grain size of the medium intrigued me. Regardles of my final decision, it won't be a "true" Jaubert system. I plan on skimming and water changes (although hopefully smaller) regardless.

 

[Rainman]

o, oh. I hear the plenum police sirens. better high-tail it out of here. jk.

 

[sambo1]

Arrest me officer, I'm guilty of thinking........... :lol: