Algae Scrubber Advanced

[Brummie]

Not even going to qualify it. ATS will help fix nutrient export issues! THIS IS A FACT! My screen still doe not grow the nice green turf but I suspect I haven't figured out the light to nutrient ratio. Who cares my sps grow and my LPS are out of control! Still think I need some info on micro nutes do if you can point it out thx.

Got a pic? I'm quite interested in screens that don't grow the conventional green stuff

 

[salty joe]

Brummie, what modifications did you make to encourage diatoms?

That little screech halfway through your video reminded me of my girl when she was little. We called her the screecher creature. A teenager now-whole different kind of creature....

 

[Chris Abbott]

Floyd, yes it must be the wrong thread.

Brummie, I posted pics in the other thread will put them up here in a minute.

 

[Chris Abbott]

This is the nasty crap I cleaned this morning! The bottom pic is lit by 4/3watt 660 red LEDs and the first side has a r/b led spotlight shining on it. So there is a lot more growth in the second side but it is pretty slimy stuff.

 

[Brummie]

Brummie, what modifications did you make to encourage diatoms?

That little screech halfway through your video reminded me of my girl when she was little. We called her the screecher creature. A teenager now-whole different kind of creature....

Made a DIY Net out of some really thick string. It's supposed to reduce the laminar flow whilst not restricting flow penetration into the algae mat. The algae still has a "wobble" so it's not severely restricted by turbulence. The flow behind the string apparently causes a weak vortex that is not as destructive to weak diatom filaments. I would point out that any benefits (and I'm not sure there are yet) may not occur until the string has been given a month or two to populate with the appropriate organisms. I think Dinos and cyano may also appear with the reduced flow.

 

[Brummie]

This is the nasty crap I cleaned this morning! The bottom pic is lit by 4/3watt 660 red LEDs and the first side has a r/b led spotlight shining on it. So there is a lot more growth in the second side but it is pretty slimy stuff.

Have you had any brown algae problems in your tank, in the recent past?

 

[Chris Abbott]

Yes, as a matter of fact I have. They have cleared up a bit. I guess the obvious idea is that it just liked the scrubber better after I changed up flow a bit?

 

[Chris Abbott]

Even thought the screen has that nice green color around the top and bottom it has never had thick hair algae growth. It is always some variation of brown, yellow, and red slimey goup.

 

[Brummie]

Even thought the screen has that nice green color around the top and bottom it has never had thick hair algae growth. It is always some variation of brown, yellow, and red slimey goup.

We'll, I've got an unproved, untested theory to screens like this. I believe the screen is inhabited by probably a filamentous diatom (brown and yellow) and maybe a bit of cyano (red) which is growing and due to its physical characteristics is sheared off the screen (known as sloughing) but not totally, allowing for regrowth. All ATS screens slough to a certain extent but it is estimated that 95% of diatom growth can be lost to the process (green filamentous loss is thought to be less than 1% in well maintained screens because it is connected to the next cell in an unbroken cellulose sheath), despite what you may have read elsewhere.This in turn makes the waterborne diatom fragments available to propagate on the screen and further dominate the system, causing regrowth of diatoms instead of GHA.

I would try putting a filter sponge or floss at the bottom of the screen to catch any sloughing, just to see if the first part of my theory is good, like I said it's an unproved theory.

Boxed in waterfalls (with raised drains) may be less susceptible to growth loss, as the algae growing across the water surface may trap a lot of the sloughing). Bubbly screens are a whole different ball game though.

I believe I have witnessed this sloughing effect in action. Here's a post I made two years ago, elsewhere;

04-30-2012

Cleared my screen again today a couple of days early to allow my air injection experiment to prove or disprove itself. When i got up this morning i saw this floating mat of growing algae in my sump.

Have never seen this before so it must have come off my screen then been formed into a mat by the small bubbles created by air injection into the pump (skimmer like). I wonder if this is normal for a new screen but largely goes unnoticed. The screen didn't look patchy but its obviously come from somewhere. The mat was about 4 inches by 2 inches by 1 inch thick. When removing the screen for cleaning i found there was another one identical on the other side of the sump. However when i removed the algae i found it shrank into the size of a small marble. The algae obviously looks a lot larger floating around in the water than it actually is. Just to be on the safe side, i have put a bit more "roughage" on the screen.

 

[Chris Abbott]

Funny you mention that, I just made a box that hangs below the screen a few weeks back. I use a square of disposable filter pad and a small bag of carbon in it. I had attributed the stuff growing on the pad to light coming from the scrubber and detritus build up. I didn't really think it could be effecting the tank algae that much, but the timing of the tank clearing up at the installation of that filter pad under the screen do loosely coinside.

 

[Chris Abbott]

I just scrape the screen with a card ATM, but have scrubbed it pretty well in the past.
I guess if it's not broke... Hope it doesn't break tomorrow?

 

[Brummie]

I just scrape the screen with a card ATM, but have scrubbed it pretty well in the past.
I guess if it's not broke... Hope it doesn't break tomorrow?

You got a close up pic of the green stuff on the screen? Does it look like single cell stuff? From here it looks like the algae?(dunno) that grows on the tanks brace members that are subject to a bit of splashing now and then.

 

[Chris Abbott]

I will post another when I pull it out to clean next time, thx

 

[Chris Abbott]

Today, not yellow today but slimey for sure!

 

[ken6217]

Tagging along.
Ken

 

[Brummie]

We'll, if nobody else is going to post, I'll stick another pic up day 8; note water depth,

 

[salty joe]

I'm guessing the water is about 6 cm. (2 1/2") deep?
Is the string doing anything for you?
What about the string under the screen?
Is this being pulsed by a pump at the bottom of the algae filter?

 

[billy mitchell]

a question on upright HOG scrubbers
the air supply ...
does it make any difference if the airline is connected to an airstone on the bottom of the screen

Or how it is done by Santa Monica scrubbers with the airline tube is cut along a horizontal length at the bottom with a 90 degree cut across the horizontal cut ...confusing ...
would there be a difference or both would do the job

 

[SantaMonica]

For upflow scrubbers, larger fast moving bubbles work best because you want to stir up the growth and allow water and light to reach into it. Airstones don't provide these large bubbles. And they clog.

Sliced airline is a cheap and fast way to get large adjustable bubbles, and if it clogs you just brush it while blowing in the tubing and bending the cut airline segments.

 

[Brummie]

SCRUBBER KILLER?

Anyone come across one of these before?

http://en.wikipedia.org/wiki/Condylactis_gigantea

Apparently it's exudates kill filamentous algae (and other algae types)

http://www.jstor.org/discover/10.23...uid=70&uid=4&uid=83&uid=63&sid=21104101151307

Abstract:
We did in situ experiments to study the influence of a water-borne substance, exuded by the reef anthozoan Condylactis gigantea, on filamentous algae. Algal biomass accumulation on experimental glass slides was significantly inhibited by the exudate. Algal spores and diatoms were present in equal numbers on experimental and control slides, but the exudate inhibited germination of spores and was toxic to developing green, red and brown algae. The algal population on the control slides consisted of early colonizers as well as later successional species and reflected the natural population. The described allelochemic mechanism will be important in interference competition between the anemone and algae. Settling of larvae in supposedly space-limited systems such as reefs is facilitated when algae-covered surfaces are open to settlement.

I wonder how many other organisms produce this level of "anti algae nastiness". May be a good enough reason to run carbon in front of the scrubber if it's struggling to get going, or if it fails after the addition of a new coral species etc. Food for thought