Akwar'eum

[framerguy]

Hi Heinz! Well, an algae scrubber is a flat, low water level area (usually highly lit) that water flows across and provides a surface for algae to grow and export nutrients. You just scrape the algae occasionally. Some of the public aquariums use very large ones. They haven't really caught on at the hobbyist level yet.

[hma]

Thank you very much Greg for the explanation, now I have understood.

Good idea, did you have a picture of it to take a closer look and is it to buy as a ready solutions in trade or is this more a DIY?

[framerguy]

Here is a close up of it Heinz



It is from a little while ago and the salt creep is from pre scrubber. It doesn't creek AS much anymore but still the bubbles burst and make a little spray. I have no idea if these are a purchasable item in the industry. They should be, I'll have to look into it! Maybe I've found a money maker!!

[Craig Manoukian]

Nice work Greg!

[hma]

Coooooool , that is really a good idea Greg. Thanks again for the close up. It is definitive a DIY, it should not be a problem to build. How is it with the noise backdrop? If I understand the principle correctly, the water has to flow a long as possible distance. Dive does the end of the algae scrubber into the water of the sump or does end it better shortly before?

[framerguy]

Right Heinz, the more surface area you can provide the better it will work, but even a very small one will be a good thing.The noise level is low, sort of a low gurgle is all. I think a spray bar would be a good addition to my present set up to help spread the water more evenly over the surface. I DIY'd it to fit my tank, it took about twenty minutes to build. It means a lot to me that you like it!

[hma]

It's so simple but really, really good ..... no, it's simply splendid!!!!!!

I use it 100% for my FO.

[CMG]

Wow, what a simple concept. This reminds me of a magic trick. There is always such an easy answer but its so difficult to figure out on your own unless the magician tells you!

I have a question though. The algae is competing for the same nutrients in the water as the chatoe so is that a bad thing? Or do they both still thrive?

[framerguy]

Originally Posted by CMG

Wow, what a simple concept. This reminds me of a magic trick. There is always such an easy answer but its so difficult to figure out on your own unless the magician tells you!

I have a question though. The algae is competing for the same nutrients in the water as the chatoe so is that a bad thing? Or do they both still thrive?

Well, I installed the scrubber on Feb 21 and have had to thin the caulerpa twice and about two weeks ago I halved the Cheato ball. The Cheato could already be thinned again. I have definately noticed less algae except Halimeda in the DT. In fact it worries me a little for my sea hares.

[tbittner]

Hair algae is pretty. Why are you trying so hard to keep it out of your DT?




Just kidding of course.

[framerguy]

Originally Posted by tbittner

Hair algae is pretty. Why are you trying so hard to keep it out of your DT?




Just kidding of course.

I was like What The..! Then scrolled down a bit

[tbittner]

I'm tired, what can I say.

[framerguy]

You've had a busy day...GO TO BED!

[CMG]

I found this article from a long time ago that seems to mention some interesting stuff:
http://www.hallman.org/filter/scrubber.html

Here is what I chose to "highlight" (sorry for the large amount but it all seemed important)

In a closed system (aquarium) denitrifying bacteria exist in such small numbers that they do not significantly reduce nitrates and nutrients to below acceptable levels for mini reef aquarium. Algae in these aquariums usually reduce the amount of nitrates and nutrients in the system but it is the unwanted blue-green slime algae and diatoms that extract the highest amount of nitrates and nutrients. These types of unsightly slime algae are the early colonisers that we find in our aquarium especially when newly setup. Species such as Caulerpa spp are usually added for attractive decoration and do have some beneficial uses. These also remove nitrates and other nutrients but being macro algae and a late coloniser to the micro algae (blue-greens; diatoms etc.) they are not as efficient at reducing large amounts of nitrates and nutrients. It is therefore the micro algae that must be kept to reduce sufficient amounts of nitrates and other nutrients. Using a biological system such as undergravel filters, canister filters, drip filters or any other filter that makes use of filter media where bacteria live and breakdown detritus should not be used because it misses out in significantly reducing nitrates and nutrients. What actually occurs is that nutrient and nitrate level builds up over time and is not reduced at all. It actually ends up being recycled with no nitrates being removed. This results in nitrate and nutrient levels not being reduced to significant proportions and if no plants or algae are found in the aquarium, there will be increased levels of nitrates and other products such as phosphates. This will result in high nutrient levels in the water and in return cause algal blooms consisting of green, red and brown slime, coating and smothering all sessile organisms. Another undesirable problem is that when these bacteria break down detritus they are also producing and giving off CO2 continuously. This results in a decrease in the pH of the water (increased acidity). For biological systems to work, the aquarist had to make frequent water changes that kept and reduced the amount of nitrates and nutrients in the water. This would no longer be required although topping up with deionized or distilled water would be required. Local tap water is too high in phosphates and should not be used. Algal turf scrubbers make use of the algae by purposely growing the micro algae on screens in shallow trays and illuminating them with a strong light source such as metal halide lamps. Water from the aquarium flows to these filters and enters them by use of a wave generator (without a wave generator approx. 50% of the efficiency is lost). The wave generator produces a constant back and forth motion, preventing the development of a semistagnant layer that occurs when a constant flow of liquid passes by a fixed object. It has been shown that a lack of surge motion results in a direct reduction in algal production. The water passes over the algal screen where nutrients, nitrates and many other types of ions are systematically filtered out of the water. As much as 0.3g to 1.2g of nitrogen (N) a day per square meter of algae turf scrubber can be removed. Even metals such as copper and ions which in significant amounts are harmful to most reef inhabitants are slowly filtered out. Even the pH increases due to the removal of CO2. The filtered water then is pumped back to the aquarium where it enters again through a wave generator mounted at the top of the aquarium. The algae turf scrubber must be illuminated by metal halide or VHO (very high output fluorescent lamps) lamps. These lamps must be illuminated for over 12 - 18 hours a day. Day/night cycles of the scrubber to that of the aquarium must be reversed to obtain reasonable results. During light conditions the algae are producing oxygen (O2) and during night cycles they produce carbon dioxide (CO2). To eliminate excessive CO2 build up at night in the aquarium the algae scrubber is illuminated to produce O2 and hence the reversed day night cycles. A turf scrubber that has matured and is running should have its screen scraped every 7 to 20 days

[framerguy]

Thanks CMG! Never worry about the size of the post in my chronicle, it's yours to add to if you want. That is some extremely interesting information. It sounds like I need to add a layer of screen (nylon window screen?) to the surface of the glass, add a stronger light system (75W MH?), and (the toughest part) add a alternating current to the surface. How the devil will I do that? I wonder about a SQWD wavemaker...probably. In my new build I may try to employ that. I was going to build an acrylic box and let the water trickle down the sides but that is unidirectional only. Hmmmm, things to ponder. Thanks again!

One of the things I disagree with in the larger article are the centrifugal pumps destroying the plankton returning to the tank. I know for a fact that they make it through.