I'm a little hazy on what exactly an algae scrubber is. TBT mentioned it in a post about reducing nitrates and I thought it sounded interesting.

Am I on the right track to think of it as a protective cage (so the tangs won't eat it) to grow macro algae when you don't have a sump?

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If it's broke, don't fix it---hide it.

Your on the right track! My idea of a good algae scrubber is actually a part in the sump that is lighted 24/7. Here you can add calurpa and such to grow at it's own pace. I had one on my 26 gallon tank, it was just a 5 gallon sump, and it grew all sorts of algae and calurpa. After about a week, my phosphates and Nitrates drop dramaticly! The algae and Calurpa will feed off of those two items. In long terms, it'll actually help stop the unwanted growth in the main tank itself. It wasn't preatty to look at, but man, it made a difference.

Over time the area started to house all sorts of creatures. Like Pods. I also added 3" of crushed coral. Then I guess you can call it a refugia by then.

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- Eric

No, you're confusing two different things. An Algal Turf Scrubber (ATS) is an outside filtration system based on a screen where turf algae are cultivated and periodically harvested (scraped off) to export nutrients (nitrates, etc.). This system is usually employed without a skimmer. There are certain benefits to this system as far as preserving more planktonic diversity in the tank and there is the possibility that this system may not create as much of a problem as a protein skimmer in removing trace elements. There is a possibility that this system may introduce yellowing compounds into the tank which could be controlled with occasional GAC (granular activated carbon) use. You might say that this would be an alternative filtration method to a protein skimmer that may or may not be better, that is probably more expensive, and that is probably more labor intensive.

The "protective cage" you are thinking about would be an in-the-tank refugium area (perhaps a corner of the tank) that is closed off with plastic lighting eggcrate type stuff to provide a safe place for macroalgae, amphipods and copepods to flourish away from the fishy predators that would love to snack on them. The goal here is to provide extra amphipods and copepods that WILL be eaten once then venture out of the confines of the safe area. Any macroalgae that grows through the enclosure will be eaten by an herbivorous fish. You could also harvest some of the macroalgae for the fish by removing one of the panels (the top) of the enclosure.

Ninong [img]/ubb/smile.gif[/img]



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Irrational Exuberance!

I am at fault here for using the wrong terminology. What I had suggested in toptanks post was exactly what Ninong describes in the latter part of his post(and what you were thinking Linda).I had not mentioned anything about pods and other critters(thus making it now a refugium) because tops concern was only to lower the nitrate levels.More than likely , over time it would have evolved to a refugium anyways.
Since we are on the subject now anyways I have another question. Would it make sense to put a small mesh bag filled with bio-balls into an algae tank and start feeding it to provide a nutrient source.I have a tank (now a refugium) that my overflows run through before they enter the sump. The caulerpa has all but stopped growing.I attribute this to lack of nutrients. My DSB has developed nicely,my skimmer produces less and less,and I see these as signs that the nutrient level is being depleted.The algae tank is lit 12 hours a day and the macro that is there is dark green and healthy looking.I have no other algae (hair,slime)present anywhere except when I make a diatom bloom, but that never makes it to the tank.The main tank is target fed a ESV spray dried phyto/frozen brine/selcon mix so not much thats put in is wasted.What does hit the bottom is made short work of by everything else.Anyone have an idea here? Sorry for being so longwinded.TBT.

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In this hobby patience is not a virtue,,,,,its mandatory.
Jim's Marine Links

[This message has been edited by the_blue_tuna (edited 12-22-2000).]

TBT ~

Check with Joaco and SPASSE, they both have experience with refugia.

Ninong [img]/ubb/smile.gif[/img]

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Irrational Exuberance!