# 8 coil glass diffuser question



## eklikewhoa (Jul 24, 2006)

i have a 8 coil diffuser set up to a diy co2 with enough pressure to get it going. 

the question i have is it suppose to be filled with water or is it suppose to be empty? with the 8coil there is a tiny opening at the beginning of the coils inside the glass bell and it has filled halfway with water so the bubbles are coming out of that little opening, witnessing this i dont see the point in having 8 coils on there. if the diffuser is suppose to be filled with water then im thinkin it might have enough pressure inside to force it to the top of the coils but how do i get it filled with water or better yet how to i get the water out?


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## Roy Deki (Apr 7, 2004)

Personaly the coils are only for looks. Doesn't matter if it has 3,5, or 10 coils...3 bubbles per second is 3 bubbles per second. With time it will have more water in it. The only way to remove the water is to stop using it and let it evaporate.


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## eklikewhoa (Jul 24, 2006)

thanks for the reply,

that is what i was thinking i would have to do to clean it.


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## AaronT (Apr 26, 2004)

Also, the disc will get some algae on it after a little while so you will want to soak it in bleach or a peroxide solution and give it a good scrub. I prefer to use old toothbrushes as scrubbing tools.


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## John N. (Dec 11, 2005)

Scrubbing the ceramic disk is not a good idea as you will get those dust and algae particles ingrained inside those tiny pores rendering those pores useless on the disk. I've seen decreased functionality (large bubbles and nonfunctional surface) on the ones where I did scrub at the disk. 

Bleach soaking (20 minutes) and tap rinsing (5 minutes) the disk only is the method to go to get your disk clean. 

-John N.


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## Roy Deki (Apr 7, 2004)

Get the Superge form ADG...it works great...better than bleach. IMHO


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## Robert Hudson (Feb 5, 2004)

> Personaly the coils are only for looks. Doesn't matter if it has 3,5, or 10 coils...3 bubbles per second is 3 bubbles per second.


That's what I have been pondering, and I was wondering when it was going to be discussed. Does the longer a bubble travels in a diffusor mean that more of the gas is absorbed? Better diffusion? I never saw any practical purpose for it. I do think it looks cool though!


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## bigstick120 (Mar 8, 2005)

Wouldnt the coils act similar to the hagen ladder? I would think that the bubbles would diffuse at least a little


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## gpodio (Feb 4, 2004)

Hi guys, I have been using these multi-spiral diffusers too and use my RO filter to rinse or fill them with water prior to use as the hose is a similar size to regular air tubing. I wash them in bleach when needed and use an air compressor to remove the water from the inside.

As for the coils' function, the bubble travels up the tube pushing the water in front of it up the coil and drawing water into the coil behind the bubble through that little hole in the bottom of the coil. Once the bubble has passed the little hole, it requires no back pressure from the CO2 tank to travel up the coil. While I'm sure there is some gas exchange occurring, the surface area is very small and the bubble is constantly in contact with the same small volume of water as it makes it's way up the coil rather than travelling through a larger volume as in a ladder. A ladder also has constant water movement around it in order to do it's job correctly. Not to mention that the water inside the diffuser doesn't really recycle with the tank's water, so even though the CO2 level of the water in the diffuser itself may be high in CO2 levels, it would not have any effect on the tank water outside of the diffuser. 

Counting the bubbles moving through one of these diffusers is fine if used for comparing between bubble rates on the same diffuser, however when switching diffsers or comparing with other people's bubble rate, I find the bubble rate to differ quite a bit. Most likely due to small differences in the coil's inner diameter between diffusers and other types of bubble couters...

The 8 coil was a little too big for my linkings, but the smaller ones are pretty cool!


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## General Tso (Aug 7, 2006)

I have an 8 coil diffuser too. I bought it used but, I believe that it originally came from AquaticMagic. I tried to fill the chamber with water using an oral syringe, but it just didn't seem to work. To fill it completely, I left it the aquarium overnight UNHOOKED to my DIY CO2 and it filled up. If I had had a diabetic syringe, I may have been able to fill it that way. I bought it because it looked very Mad Scientisty and I am pleased with it, but it is a little big for my 16 gallon. My bubbles don't coil around, they come out the hole in the bottom and lineup at the top of the diffuser.


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## eklikewhoa (Jul 24, 2006)

That's what I have been wondering, am I suppose to fill it with water. 

Its halfway filled right now and the bubbles come out through the bottom hole and does not go through the spirals at all. I plan to give it a cleaning and fill it with water to see how that works.


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## bigstick120 (Mar 8, 2005)

Thanks for clearing that up gpodio, makes perfect sense


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## newguy (Mar 18, 2006)

Roy Deki said:


> Personaly the coils are only for looks. Doesn't matter if it has 3,5, or 10 coils...3 bubbles per second is 3 bubbles per second. With time it will have more water in it. The only way to remove the water is to stop using it and let it evaporate.


i dont think that's true, i have a diffuser that's like 10 coils and it works very well. You can visually see the bubbles getting smaller and smaller as it goes up the coils, if it were a bit longer the bubble would dissolve 100%. I think aquatic magic has the same concept no? except they shortened the coil and put a disk on top of it.

here' a video of the the version i have at work:

http://www.happyreward.com/images/co2.avi


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## General Tso (Aug 7, 2006)

Well, this evening some of the bubbles started sticking to the coils and spiraling around. I just filled the diffuser to the top with h2o last week, and I am thinking that perhaps it is a little like the hagen ladder. The hagen ladder tends to burp bubbles for a few days until it builds up a biofilm and then the bubbles stick. I hope this is the case, because the spiraling bubbles look sweet, and when I bought the diffuser, I was anticipating it doing this.


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## eklikewhoa (Jul 24, 2006)

i was hoping that the co2 actually traveled through the spirals cause that would be awesome looking. 

oh well as long as it works it still looks cool.


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## gpodio (Feb 4, 2004)

Newguy, I can't see the top of your diffuser, but yours looks like the coil is exposed and therefore it is drawing in water from the tank, not a sealed chamber as in the model shown here:
http://img366.imageshack.us/img366/7268/5coil6om.jpg
Is that correct? If so, then your coils are the reactor, just like in a ladder.

Eklikewhoa, in order for the bubbles to travel up the coil without resistance, the water level inside the diffuser needs to cover the top of the coil. Half filed, the bubble would have to push the water in front of it above the water level which would cause resistance, therefore it chooses the easy way out. Mine have always started working within minutes, however the biofilm idea also makes sense.

If you leave the diffuser unhooked in a glass of distilled water it should fill up on it's own overnight. I found that filling it with RO/DI or distilled water helps keep it cleaner on the inside.

Hope that helps
Giancarlo


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## eklikewhoa (Jul 24, 2006)

wow i missed the video. that looks super cool!


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## newguy (Mar 18, 2006)

gpodio said:


> Newguy, I can't see the top of your diffuser, but yours looks like the coil is exposed and therefore it is drawing in water from the tank, not a sealed chamber as in the model shown here:
> http://img366.imageshack.us/img366/7268/5coil6om.jpg
> Is that correct? If so, then your coils are the reactor, just like in a ladder.
> 
> ...


yes i think you nailed it. Mine has an opening on the lower end to draw in water, which i guess forced the co2 bubble to go up the ladder. The version discussed here does look to be completely sealed at the bottom.


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