Plastic Canvas and Mold-Release Wax Coating

[Floyd R Turbo]

I found this conversation on the Algae Scrubber Advanced thread on RC posted on 2/15

http://www.reefcentral.com/forums/sh....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]

Naughty SM !

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]

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]

Any molded part uses wax. I just scrub it off.

[Floyd R Turbo]

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]

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]

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]

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]

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]

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?