Algae Turf Scrubber ?

According to the info from posts of other users you should roughen it up to the extent where there aren't holes anymore but that seems meaningless, why not get a solid piece of plastic and roughen it. Which count canvas is more popular, 5,7,10 ?
 
I didn't want to go silent here but I can't help much with the specifics on this one. I used regular gray window screen until my other algae took hold. I am really lucky. Now, I don't have to use a screen because of the type of algae that I am growing. It grows right on the relatively smooth plastic at the bottom of my dump bucket and it stays separate. I just grab a hand full or two and I'm done.

With regular turf algae, I think that you need the height of the screen. You scrape virtually all of the algae off of the very top of the surface where the tool comes in direct contact with the screen. When you scrape the course screen, it leaves algae of different lengths down in the cells or openings in the weave.

In the old days some people used two screens, sowing them together at several points. Then, you wouldn't be scraping away 100% of the algae along with it's roots. When you clean the screen some of the very top contact points are scraped away along with the algae, leaving nothing to grow back. You need to leave a five o'clock shadow, so to speak.

Roughening up the screen or dimpled plastic is important even though it already appears that the surface is not smooth. The roughening makes micro ruts and grooves for the algae to take hold of. Time will make more micro grooves but this will give you a much needed head start.

Hopefully, someone will be able to help with some of the best stuff that is available now days. Of Course SM's sight could be helpful.
 
You mean the grey fly screen ? That's fiberglass with a pvc coating. How do you avoid tearing it up when you scrape the algae off ? I am trying to find a local source of a tougher plastic, I don't want to ship sewing canvas overseas :).

The whole idea of scraping is to remove the green algae that covers the turf (red/brown). Too much green will hamper the turfs growth and will not be beneficial. That is why when scraping you shouldn't scrape everything off, that's asking for a crash.
 
I want to drive a point home. Not because you are wrong. You actually make a good point but for those that don't know much about algae turf scrubbers, I'll take a little side journey. I don't (personally) worry about a crash AT ALL!

Again, I'm no expert. This is just a layman's observation but in the 90's, bacteria was a bigger player in nutrient control. The wet dry filter was much more popular than they are now. Live rock was big but this was before the wide use of calcium carbonate sand beds. Now we use some sort of algae or bigger better skimmers.

In those days, wet/dry or trickle filters occupied a bigger portion of the nutrient control system. Large bacterial blooms in the wet/dry box sometimes consumed so much oxygen that some of the inhabitants in the tank died. This caused the water quality to decay and even more of the population died. In a few hours, you could go from a beautiful thriving tank to a milky white dead zone called a crash!

Bio balls are not bad but with the scaling back of the plastic media and the introducing of more coral gravel and refugiums, the bacteria population is more divers and stable so oxygen levels are less likely to drop precipitously.

Users of vodka are taking the strongly stated advice to start very slowly and to progress carefully to their optimum dosing levels. This is because of the potential of a low oxygen induced crash.

If you were to take too much algae off, you probably would severely reduce the amount of oxygen input but you would still have a heightened level of air exchange as the water went through the shallow scrubber. You won't get anything in the scrubber that consumes the oxygen in the tank. Instead you would see the nutrients slowly rise and your corals would start to look unwell, giving you plenty of warning to start running your tests.

Now on to what I used for a screen and the amount of algae to remove. Yes I used regular grey fly screen. I used a wide spatula to scrape the 6 inch wide screen. …and YES, it did not last for ever, about 6 months. It was Definitely not the best choice but it worked. We have much more to choose from now. I figured that the 8 year old spores or roots or what ever, from my last use of the dump bucket, would come back in my new tank. The plastic surface had micro abrasions that supported the algae before. I figured that it would again. Therefore, even though I had more choices, I just used the fiberglass screen with a pvc coating for the short term.

You do want to harvest the canopy layer down through the mucilage layer. Cleaning the algae down to the basal filaments will unleash the highest levels of growth but if the roots are gone as well, then you will have to start all over again with spores.
 
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Yeah, you'll want the plastic canvas quite rough. I don't have any pics of how rough mine is, but the idea is to be able to leave the holdfasts, etc. after cleaning and to make sure the algae can grip the substrate in higher water motion. Basically, the rougher the better. I'm not sure about the holes comment, but you should look to make the screen look fuzzy, for lack of a better descriptor. If you think you've roughed it enough, do it more. I think I probably spent about 2.5 hours total (over several days to a week) using a hole saw bit and grinding it around by hand. That's gotten the best results out of anything else I've used. Don't use a drill, either, since doing it by hand still seems to yield better results, IME. A bit labor-intensive, but the end results are better.
 
Taking your ATS offline manually or with a solenoid and timer will improve efficiency.

During the dark cycle (daytime in the case of a reverse photoperiod ATS) the algae produces Co2 and consumes O2, thus lowering PH and dissolved oxygen levels in the display tank. During respiration (dark cycle) the algae "leaks" nutrients (Phosphate, nitrogen, silicate, and heavy metals) back into the system water. The release of bound nutrients is at a much smaller rate than absorption during the daylight cycle, but a problem nonetheless.

If you take the ATS offline an hour after the ATS light cycles off, and put it back online (open to display/system water) an hour after the ATS lights turn back on 6 hrs later (18 hrs on 6 hrs off), you will give the algae culture time to absorb the nutrients lost during the dark period and reach the photosynthetic compensation point. This will give you a net result of a higher PH and better nutrient uptake.

Your fish produce more than enough Co2 for coral photosynthesis, so the Co2 generated by the ATS during its dark/night period (the corals day/light period) is not needed.

Plankton colonies in the ATS will benefit from diminished flow during the dark cycle as they are much more active in the dark and prefer slow moving water during their nightly swim.
 
If you take the ATS offline an hour after the ATS light cycles off, and put it back online (open to display/system water) an hour after the ATS lights turn back on 6 hrs later (18 hrs on 6 hrs off), you will give the algae culture time to absorb the nutrients lost during the dark period and reach the photosynthetic compensation point. This will give you a net result of a higher PH and better nutrient uptake.

Plankton colonies in the ATS will benefit from diminished flow during the dark cycle as they are much more active in the dark and prefer slow moving water during their nightly swim.

Why would you wait for an hour after lights out (daytime) to stop the flow and wait for another hour after lights on (night time) to restart the flow ? Why not put both flow and light on the same timer ?
 
Why would you wait for an hour after lights out (daytime) to stop the flow and wait for another hour after lights on (night time) to restart the flow ? Why not put both flow and light on the same timer ?

For reasons of economy and simplicity they could and probably should be on the same timer. I was just pointing out that algae will not drop below the compensation point (even consumption and production of Co2 & O2) until an hour after lights out and will not reach it again until an hour after the lights come back on. You would get two more hours of ATS filtration for every 24 hour cycle, but I agree that less is more when it comes to timers and gadgets.
 
The main practical restriction is that with the usual lamps, the algae won't fare well if illuminated without flowing water. I did this without thinking about it to run some maintenance on the feed pump, which resulted in killing some of the algae, especially the strands closest to the light source. This happened in less than an hour.

The other thing is that from what I've seen and read, nitrogen uptake, while greatly reduced, continues without photosynthesis. There's also evidence of this with phosphorus in algae. Nothing I've seen has shown a net nocturnal release of either, but I've also had a hard time finding much info.
 
Here's my new horizontal. Not complete. Need lights yet and some screening on there. What do you think about the idea of a layer of grout on there instead of the plastic canvas?
My skimmer has been off my tank for about two weeks now and it loves it. HA is starting to show but hopefully my ATS will work and take care of it for me.
I designed it to keep my refugium and use the overflow for feeding it. There is 600+gph running over the top of it. I love that it's quiet. It's about as loud as one of those table top fountains which when the doors are closed you can barely hear it. I do not miss my skimmer. So. The good ,bad and ugly.





 
The main practical restriction is that with the usual lamps, the algae won't fare well if illuminated without flowing water. I did this without thinking about it to run some maintenance on the feed pump, which resulted in killing some of the algae, especially the strands closest to the light source. This happened in less than an hour.

The other thing is that from what I've seen and read, nitrogen uptake, while greatly reduced, continues without photosynthesis. There's also evidence of this with phosphorus in algae. Nothing I've seen has shown a net nocturnal release of either, but I've also had a hard time finding much info.

Sounds like the algae got smoked.
 
Why would this be the case? I've seen turf algae out of the water for low tide for hours,

Depends on the algae. True intertidal/littoral turf species will be a lot more resistant to this, but not every scrubber actually grows these. Mine tends to grow more Derbesia, which isn't nearly as resistant, IME. If you were to try what mr. wilson suggested, be sure you have algae that can tolerate it.
 
Why would this be the case? I've seen turf algae out of the water for low tide for hours,

As intense as sun rays may be I think that his lamp at close range had too much intensity for his algae.

I think a heat producing lamp 4-5 inches away from me would have a higher heating effect than the suns rays.
 
Algae survival when it is out of water has a lot of variables. You will see clumps of algae that do just fine when the tide goes out in one place and very near by it will die. Lights can be very hot and can cook algae pretty quickly. I hope that people use compact fluorescents. Either the ones that are long and flat or curly. I have even seen newer ones that just look like a bulb but they are much bigger and much stronger.

whoadude
I like your set up. It is very basic and will probably work just fine. In addition to the canvas or screen, I see that you have roughened the plastic on the bottom of the tray. It will also attract the growth of algae as well. If you later decide to discard the canvas, there MAY be a problem when you scrape it. You may end up scraping almost all of it off and it may take too long for it to grow back to a productive length. On the other hand you might be able to grow the right kind of algae that you can just pull off of the plastic. It would be nice if you could grind deeper depressions so that you would leave more of the roots in tact if you scrape the plastic.
 
I have never used it for algae culture, but Enkamat may prove to be a good growing media as it provides a better holdfast (grip). http://www.aquaticeco.com/subcategories/3107/Enkamat-Nylon
http://www.colbond-geosynthetics.co...roducts/enkamat/productfamily/1§enkamat.html

Alternatively a calcareous flooring tile will provide the right chemical conditions for algae growth as it will act as a phosphate sink and reflect light back up into the algae culture. They are rough so there is a good surface for the algae to attach.

After you trim the algae it tends to "bleed" or "leak" which releases bound nutrients and spreads algae spores into the display tank. Having the ATS on a shut-off or bypass system as I suggested above will help the algae "heal" before it is put back on line.

I would use several screens or plates and clean only one at a time to keep production going and minimize fluctuations in growth.
 
I like the Enkamat type of approach in the 1/4 inch version. Aquatic pointed me to an aquarium divider as a product that is being use by others for scrubber screen but I couldn't see much detail. I have heard that the tiles work for some people as well.

I also agree that harvesting only part of the algae at a time can be a good idea. I used to use this method when I had time. I hope however, that people don't get too caught up in other details that may or may not help in the big picture. As I have said before. Scrubbers are very forgiving.

Although I feel that I have a great design and it meets of all the criteria of a true ATS, I know that there are a tons of other designs that work great for other people.

I can see that scraping algae off, crushes the end at the point of removal. I would think that if "bleeding" does happen, it would be accompanied by rapid "clotting" or "healing", being that turf algae has specifically evolved to stand up to and even flourish under heavy predation. The fastest growth happens right after predation and probably grow in erect response to crushing and shearing so the strands must have a mechanism to be ready to go right away. For that reason, I would hope that most of any leaking would be washed away when you rinse it in fresh water. If leaking did happen after the screen is back in the tray or holder, when the water comes back on line, that leakage would then be washed into the tank anyway, wouldn't it.

Studies in the future my demonstrate that this point is true but I would think that it would still be a small point in the big picture. Never the less it is fun to play with all of the "what if's" in an effort to find the perfect scrubber design and maintenance technique. This seems like a great experiment to try and report on.
 
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