Refugium discussion

I would say absolutely, but I doubt 10% rule would be enough.

at 50% it I'm willing to bet it would work.

 

An important thing to keep in mind is that the skimmer is removing DOC’s and the refugium is removing nitrates. DOC’s break down into nitrates. But there are adidtional benefits from skimming and from a refugium that one can not offer over the other - I like this little turn on this discussion. Anyone care to elaborate on the secondairy benefits of the refugium and skimmer ?

 

Sort of, but not really. And there are some claims against skimmers that have not been found to be true in real life. Mostly coming from ATS proponents... yet many continue to run a skimmer even if they have a ATS.

One such claim that has been debunked time and time again is that skimmers remove trace elements... so that is not worth talking about. Do skimmers remove food... well yes they do. Every bit of organic material is food to something. But skimmers do not remove everything and they do not remove DOCs. They remove hydrphobic DOCs... which are generally protiens. And a skimmer does remove particulate matter as a mechanical filter, but not all matter. I ran fine filters and took them out and yes there was more particualte matter in my tank. And I had a beast of a skimmer. So while it can remove some particulate just from catching it up in the bubble column... it is a poor mechanical filter... there is much better.

What skimmers do is remove some of the waste before it is broke down... every bit of skimmate and every bit of material cleaned out of the neck would rot in the tank until it was finally broke down into base nutrients. A skimmer is simply a way to lessen the waste load put on the system.

Macro algae can most definitely be grown to soak up huge nutrient levels.... however, first the waste must be broke down to N an P to begin with which means it is in the water column already. Second, nutrient uptake is determined by light out put.... light drives photosynthisis... so yes you can grow enough macro algae, and yes you can harvest a waste basket full of it weekly.... but that comes at the cost of light driving it and the power that uses... and having large amounts of N and P available. Not to mention a larger are to grow in... although probably combining most skimmer compartments with fuge compartments would be a lot of room.

So why not use a skimmer to remove some of that waste with it's little 20 watts of power, and run lights to mop up the little bit that's left... instead of running a macro algae grow operation so you can harvest a ton of it and throw it away? Relatively speaking.

 

OK, then let's keep this discussion clean and use proper terminology. Refugiums do not remove nitrates. Macro algae, and DSBs remove nitrates. A refugium is nothing more than a box without predators to grow pods in.

One thought I have been willing to entertain in the past is that a "refugium" can mean a safe place for macro algae to gro without being eaten. However, most macro algaes used are not eaten once in the main tank and become a nusance. I mean we would not even need a special place to grow macro if it grew in the display and fish ate it to keep it down and then we just filtered poop. Instead of feeding fish we would just fertilize algae.

A secondary benefit of Refugiums is removing nitrates by way of macro algae export and DSBs providing low oxygen areas. The primary purpose for a Refugium is to provide a place for pods to grow so their larve can feed corals.

And no, skimmers can't grow pods, and fuges can't remove waste. One secondary benefit of skimmers is oxygenation of the water. However, studies have shown photosythisis provides the Lion's share of this and mechanical means can barely compete. A skimmer will provide oxygen at night during low oxygen consumption periods to be enough while photosythisis is not taking place.

Many run a fuge on a reverse cycle to help PH and oxygen... however I never saw a difference. My fuge grew so little cheato it didn't have any effect on PH at night.... and my little 23w CP bulb could not compete with 720w I ran during the day and all the micro algae being produced.

 

So you're saying my best bet would be, if I were a person trying to get the most "food" into my refugium, would be likely to turn off the skimmer for an hour while feeding, and afterwords turn it on again to clean up the waste.....

 

That would, to me, be the best of both worlds, get plenty of food product spread around the tank and Fuge, and after, continue where I left off....

 

What i have done

I believe a refugium is much more than a box to grow pods. I do agree that growing microfauna should be the main reason for installing one, and using macro algae to remove nutrients(disolved organic compounds ie.) should also be included if refugium size to tank size allows this to happen. I have spent many years running large refugiums and have seen first hand their ability to help water quality, supply food for main tank, and be just fun to look at and watch.(they are a great learning tool, i believe)

I have used both deep sand beds and rubble rock with some aqua scaping rock formations. I like rock rubble 2" to 4" size with sand mounds one back corner area maybe 1/3 refugium space. I do not slow flow, my systems have always been high flow it works well for me. Nutrients are in the water not the flow so how ever you want to run it is your choice.

I also include pep. shrimp many as i can, they carrie eggs twice a month and work well. They will also clean some pest from main tank rock placed one at a time in refugium.

How ever we view our refugium is our choice and also how clean we keep it is our choice too. The true test is how well it works with the main tank and a easy way is to watch your fish, they will show you if it's feeding the main tank.

Lighting for me was always MH or VHO, never have used LEDs but plan to.

What order?

Here is how i have always run mine:

Skimmer 1st - Refugium second - Return third - High Flow - High Light

No matter which way you build it...........Have fun and take time to enjoy!!!

Last keep in mind that setting up a tank with dry rock and a couple of pieces of live rock opens you up for a greater chance of a microalgae problem. Colonization of microalgae can/will spread at a much faster rate than organisms present on live rock. Unless your new refugium is huge and already running kick ___ it can't stop this.


Thank You,

 

There really is just no point. The fuge get some raw food and it gets a lot of poop. It gets plenty. In fact some actually need to filter or reduce flow because too much waste collects in the fuge. You can easily suffocate a sand bed if too much waste builds up.

I never bothered to turn my skimmer off at feeding. When I did turn my simmer off was before going to bed. It was lights out, I would dose my rotties, oyster eggs, or phyto, and then turn my skimmer off for a couple of hours by way of feed timer. The corals would all be extended and hungry and I wanted them to feed for a couple of hours instead of the skimmer getting it.

 

I never meant to mean that a fuge can't be more than a box to grow pods... what I'm saying is that it is ideal to place other "components" in to perform other functions. I just like to be clear what each of those components jobs are and why you want them. Putting all those components together... DSB, macro algea, and a place free from predation... then you have what has become known as a "fuge" these days. I just feel it is important to stress the roles of each of those components and that you do not "have" to have them to have a"refugium". I apologize if some find that to be splitting hairs.

One thing is that while you have run "high flow" and say it's fine... do you actually know that. Many in this hobby say what they do works fine, when in fact they have not tried anything different and do not know if another way would not be better.

I will admit though, that being involved in this hobby can at times be contradictory. We seem to get into these debates about what way is "best" and doing that way is "bad".... yet the fact is that there is a great variety in how things are run and all can be successful. More than lickely the details are less important that the husbandry and how well you take care of your system.

Having said that, whether it is "right" or not I don't know. What I do try to do is look at the pros and cons and come up with the "best" way or best bang for the buck on paper to give me the best chance at making a meaningful impact. There are plenty that run everything in line either skimmer first of fuge first. Bottom line though is that "on paper", fuges have been shown to not require that much flow, we do know skimmers can remove larve and small food, and that placing the return in the middle and controlling flows to both skimmer and fuge is not that hard.

Now I can't quantify how much "better" that is in real life, but to me the advantages of placing the return in the middle seem good enough that when I build my sump/fuge that I recommend building it that way. Perhaps good husbandry can make up for less than ideal design, but I try to shoot for good design and good husbandry.

Really not trying to say I'm right so please don't take me that way. Just another example of how cool and diverse life is and how it can thrive in a variety of ways. We all have fun putting these things together and see our work rewarded with a vibrant tank teeming with life. Pretty cool. And fuges are a pretty cool part of that. Much better than just filter floss and a canister.

 

Skimmer
Raise pH levels (via off-gassing of CO2)
Off-gasses Ammonia
Raise DO (Dissolved Oxygen)
It's partially chemical filtration and partially mechanical filtration. Bits of uneaten fish food and fish poo are removed mechanically. DOC's are removed chemically.
Remove organic and inorganic phosphates.
Removes Gelbstoff
Can be used to export bacteria (i.e. Carbon-dosing)

Refugium
Can be run counter cycle with the tanks lighting to stabilize pH
Fun to look at
Helps remove phosphorus and nitrates
Can raise pH level (macro absorbs CO2)
Increase in DO (Macro converts CO2 into Oxygen)