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Floyd R Turbo
04-10-2013, 08:00 AM
I found this conversation on the Algae Scrubber Advanced thread on RC posted on 2/15

http://www.reefcentral.com/forums/showthread.php?t=2028045


Why do scrubbers take so many weeks to work well?


Attachment.

Plastic canvas is coated with mold-release (wax), and this stuff needs to be degraded away before algae attaches well (washing with soap will help too). Also, slippery plastic is used to make the canvas, so as to allow sewing needles and yarn to easily slide through the holes. These two things have been solved in my next scrubber version; they are harder to diy but they provide much faster and stronger attachment in fw and sw, and they leave a good bit of growth behind automatically.

Seems to me that this is big news, very pertinent information that would seem to apply to the entire algae scrubber community. You've been holding out on us SM!! Where did you get this information?

Is this mold-release wax on the surface only, or is it impregnated into the material? If it is the former, doesn't roughing up the screen remove most of this?

What is the mechanism that degrades away the wax? Why does soap help?

On the soap comment, I would note that soap or any soap residue needs to be adequately removed before introduction into the aquarium. Most people would not even think twice about that, but there's always that one guy that doesn't know that soap and aquariums don't mix. Spraying with bleach and scrubbing to remove the soap residue would be required.

Is there another mechanism that could be used to quickly degrade this mold-release layer away, like a chemical dip, such as Muriatic Acid, Bleach, Hydrogen Peroxide, etc, after and/or before roughing up?

Devs
04-10-2013, 10:48 AM
Naughty SM :rolleyes: !

I cut two pieces to the size I need and glue them together, this also gives rise to leaving a decent amount of growth in the deeper cavity, it also makes the screen very stiff.

Floyd R Turbo
04-10-2013, 10:54 AM
I never saw the need for multi-layered screens, and they really aren't recommended IIRC. Thicker screen with more growth in the cavity would tend to block light that otherwise would transmit through and support the 'roots' on the other side - at least for the first few days of growth. After you get to a certain thickness of growth, then you lose that transmittance and that's when root death accelerates.

SantaMonica
04-10-2013, 12:35 PM
Any molded part uses wax. I just scrub it off.

Floyd R Turbo
04-10-2013, 12:48 PM
That makes sense. However, if this wax coating is basically just on the surface, wouldn't the roughing-up process just remove most of this? All that would remain would be the area of the screen in the holes that never got 'hit' with the saw blade. With the amount that I rough up my screens, I can't see how this would matter much.

I'm thinking that the physical difference in material between the canvas and the green grabber is more pertinent than the absence of a wax coating.

BTW what is that green grabber material?

SantaMonica
04-11-2013, 04:54 AM
Roughing up without washing will just push the wax into the material.

The GG material is not finalized yet... trying different sources.

Floyd R Turbo
04-11-2013, 09:21 AM
I could see that being partially true, but when I rough up a 10 x 13 piece of canvas I end up with about 1/4 cup of shavings, so I think it's fair to say that at least a fair portion of the wax gets physically removed. But it's good to know that a good scrub and soak might make the curing process speed up a bit.

FYI for anyone curious, cleaning with soap will leave a residue that must be removed by spraying with a bleach solution and scrubbing again. I might give this a shot and see if it makes a difference.

What about just boiling the screens? That would dissolve the wax...but might turn the screen into a mess too!

kaskiles
04-11-2013, 08:29 PM
Try a soak in Oxyclean and a rinse of RO/DI. The OxyClean (with no additives), makes a high pH, hydrogen peroxide solution; wax shouldn't stand a chance.

Floyd R Turbo
04-11-2013, 09:29 PM
I haven't had a chance to search for wax-eating chemicals. That's a good one, thanks for the info.

So I'm not a 'wax expert', but does a high pH H2O2 solution indeed dissolve wax?

FWIW, I took my kid's little digital magnifying glass thingy called an "Eyeclops" - got it at Toys-R-Us one Christmas - and looked at a screen before cleaning, after just scrubbing, and after scrubbing with soap followed with bleach. 400x magnification but really cheesy resolution. I couldn't really tell a difference.

Going to see if I can get use of our local school's marine biology lab and use a good microscope. I wonder if this is really even an issue.

Ace25
04-11-2013, 09:44 PM
After hours of searching and asking around, I can't find anything about wax being used in the Mfg process of the screens we use. As a test, I have a few sheets of brand new screen laying around. I boiled a large pot of water and then soaked the screen in the water for a few minutes to soften it up. If there was in fact any wax or oils it would have released in the 200+ degree water and I should have been able to easily spot it on the surface of the water, but it was crystal clear. http://en.wikipedia.org/wiki/Plastics_extrusion

So, Santa Monica, since you made the statement, can you provide proof that the screens we use have what you say is on it?

Garf
04-12-2013, 04:02 PM
After hours of searching and asking around, I can't find anything about wax being used in the Mfg process of the screens we use. As a test, I have a few sheets of brand new screen laying around. I boiled a large pot of water and then soaked the screen in the water for a few minutes to soften it up. If there was in fact any wax or oils it would have released in the 200+ degree water and I should have been able to easily spot it on the surface of the water, but it was crystal clear. http://en.wikipedia.org/wiki/Plastics_extrusion

So, Santa Monica, since you made the statement, can you provide proof that the screens we use have what you say is on it?

Strangely, I did the same searching Ace. I came up with the "Bollocks" theory. Ie "what wax".

Ace25
04-12-2013, 04:11 PM
Well after seeing SM's new signature banner, it all makes sense now. Still bollocks though about the screens.

Garf
04-12-2013, 04:18 PM
http://i1269.photobucket.com/albums/jj597/Garf1971/33cb01e764bd53fbcb15b0b2556331ad_zpsd53728e2.jpg

Floyd R Turbo
04-13-2013, 06:49 PM
Well I spoke to a couple of people and one of them contacted a chemistry guy (a teacher or professor, I believe). He said to "submerse the net [sic]. Boil in water. You won't see wax dissolve. Let water cool to room temp and you will see wax crystallize out of the water as it cools"

Trying this as we speak

Floyd R Turbo
04-13-2013, 08:04 PM
Well, confirmed. Total BS.

Bilk
04-13-2013, 08:18 PM
Like everything else I've ever put on line in the system, they get a good rinse with vinegar and hot water. Wax and all should be removed with this.

Bilk
04-13-2013, 08:24 PM
After hours of searching and asking around, I can't find anything about wax being used in the Mfg process of the screens we use. As a test, I have a few sheets of brand new screen laying around. I boiled a large pot of water and then soaked the screen in the water for a few minutes to soften it up. If there was in fact any wax or oils it would have released in the 200+ degree water and I should have been able to easily spot it on the surface of the water, but it was crystal clear. http://en.wikipedia.org/wiki/Plastics_extrusion

So, Santa Monica, since you made the statement, can you provide proof that the screens we use have what you say is on it?
I believe any of the plastic products we utilize have residue from the manufacturing process - that includes oils and other chemicals. Most every protein skimmer directions say to rinse with vinegar and/or hot water prior to use. Just a basic principle to employ when integrating a foreign material into a reef system.

Ace25
04-13-2013, 08:32 PM
Thanks for confirming it Floyd. Always good to have multiple people try things to confirm or deny results.

Here are 2 vids that speak for themselves. If there was any type of oil or wax I should have been able to at least see something on the surface when it cooled.


http://www.youtube.com/watch?v=VJKbozNEMbg
http://www.youtube.com/watch?v=iVw5KHZLfdI

Floyd R Turbo
04-13-2013, 09:40 PM
Yep I had a piece that was 3x4 and submerged it in boiling water for about 3-4 minutes, held it down with a fork, then "slid it out" along the edge so that it wouldn't possibly allow the wax to cling back onto it, then I let it cool all the way down to room temp and saw nothing at all on the surface.

I think it's very safe to say that there is no wax residue on these screens.

SantaMonica
04-14-2013, 04:23 AM
Also, the screen is made from slippery plastic, so as to allow sewing needles to pass through easily. It might even be the no-stick PTFE that cutting boards are made of.

Floyd R Turbo
04-14-2013, 07:28 AM
I contacted Darice and they have told me, thusfar, that "Item 33900-1 is made of linear low density polyethylene, commonly called LLDPE" (that's the 10x13 #7 clear screen) which will not be affected by a quick cleaning process. I asked about the wax residue and I haven't heard back yet.

I posted this on RC but forgot to include it here. It is not PTFE.

PTFE is Teflon and they do not make cutting boards out of pure teflon, that is a non-stick coating.

Floyd R Turbo
04-14-2013, 07:38 AM
Another thing, irrelevant of how rough the material is initially, once the algae gets a foothold, it stays well attached. So the only difference here is how quickly it gets attached. I've had several customers have screen go from bare to full green in 5-7 days and others take months. Every system is different and this translates to differences in scrubber initial growth. So you can't throw one good one up as an example for everyone to have expectations for theirs unless you have another one in the same system to compare to.

Ace25
04-14-2013, 08:32 AM
Another thing, irrelevant of how rough the material is initially, once the algae gets a foothold, it stays well attached. So the only difference here is how quickly it gets attached. I've had several customers have screen go from bare to full green in 5-7 days and others take months. Every system is different and this translates to differences in scrubber initial growth. So you can't throw one good one up as an example for everyone to have expectations for theirs unless you have another one in the same system to compare to.

http://thatschurch.com/wp-content/uploads/2012/09/tumblr_maq77ecMHG1qejf6u.gif

alum
04-15-2013, 01:05 AM
Another thing, irrelevant of how rough the material is initially, once the algae gets a foothold, it stays well attached. So the only difference here is how quickly it gets attached. I've had several customers have screen go from bare to full green in 5-7 days and others take months. Every system is different and this translates to differences in scrubber initial growth. So you can't throw one good one up as an example for everyone to have expectations for theirs unless you have another one in the same system to compare to.

is it depend how many nutrient in our tank that algae can consume?
more nutrient more grow ?

how to attract algaes want attach to the screen beside screen roughed?

RkyRickstr
04-15-2013, 01:48 AM
Not necessarily.. we still dont fully understand why some screens take off and others dont.