Octopus Skimmer Mods - Page 38

coryjac0b · 02/09/2007, 09:20 AM

is the gate valve mod needed if i plan on running the skimmer externally from my sump?

Avast Marine · 02/09/2007, 10:30 AM

Quote:

Originally posted by coryjac0b
is the gate valve mod needed if i plan on running the skimmer externally from my sump?

Not at all. The DNW comes with a ball valve and that is plenty for a recirc skimmer.

markywmson · 02/09/2007, 02:36 PM

Quick question... I did the mesh-mod with 3 layers, seems to be working well so far. Those who have done it and had it running for awhile... how often (if ever) do you need to rinse/clean the mesh out?

Thanks
-Mark

Maeda · 02/09/2007, 04:40 PM

I just got a NW150, and couldn't wait longer then a week before playing with it.

so,
I bored out my 90 degree elbow after the pump
I removed one of the NW's and put 3 layers of GG on the impeller

After this the pump looked like it was pushing way way way more water, so i decided to enlarge the venturi.

I drilled through the stock plastic ridgid tube and jammed a 1/4" airline through (blocking off the wtock 'elbow' portion) so no it just goes straight down blocking off some of the water inlet.

Now things don't seem to be working better... This just made my venturi very very VERY loud.

Any thoughts?

hounddog01 · 02/09/2007, 05:39 PM

Quote:

Originally posted by Maeda
I just got a NW150, and couldn't wait longer then a week before playing with it.

so,
I bored out my 90 degree elbow after the pump
I removed one of the NW's and put 3 layers of GG on the impeller

After this the pump looked like it was pushing way way way more water, so i decided to enlarge the venturi.

I drilled through the stock plastic ridgid tube and jammed a 1/4" airline through (blocking off the wtock 'elbow' portion) so no it just goes straight down blocking off some of the water inlet.

Now things don't seem to be working better... This just made my venturi very very VERY loud.

Any thoughts?

I have the NW-200 and do not believe the problem is with pulling too much water rather pulling too much air. After clamping down the airline it started to pull more air. I have ordered a new prop to do the mod with. I want to make sure that if I mod something I can atleast go back to where I started.

Avast Marine · 02/10/2007, 08:53 AM

Quote:

Originally posted by Maeda
I just got a NW150, and couldn't wait longer then a week before playing with it.

so,
I bored out my 90 degree elbow after the pump
I removed one of the NW's and put 3 layers of GG on the impeller

After this the pump looked like it was pushing way way way more water, so i decided to enlarge the venturi.

I drilled through the stock plastic ridgid tube and jammed a 1/4" airline through (blocking off the wtock 'elbow' portion) so no it just goes straight down blocking off some of the water inlet.

Now things don't seem to be working better... This just made my venturi very very VERY loud.

Any thoughts?

It's best to only do one change at a time so you can observe the change it makes.

Maeda · 02/10/2007, 09:53 AM

I did do them one at a time, its just truncated for ease here. The real problem i'm having is that after I goofed with the venturi, I think it's not skimming as well..... and I was wondering why.

Avast Marine · 02/10/2007, 12:23 PM

Sounds like you reduced water flow and thus reduced airflow as well. Since you already opened up the venturi, I would get a 1/8" mpt to 1/4" barb fitting and tap the venturi hole and put in the fitting, then connect your airline to that.

Maeda · 02/10/2007, 07:38 PM

Ah, I guess I cut the water flow too much with that huge airline..

So for future skimmer mod endeavors, its not a good idea to cut water flow?

I was thinking restricting the intake would force the pump to pull more air, drying out the mixture...

Maeda · 02/10/2007, 10:37 PM

I was ****ed off today. My original venturi mod didn't suck. Well it sucked but not air.

SOOOOOOO I came up with a new venturi octopus mod.

I bored out one hole, and then the 90 degree hole facing the pump. The bit was 'too large' and it broke through half the pipe wall. I then glued air line to what was left of the pipe wall and gently pulled it 90 degrees up to the silencer.

My skimmer IMEDIATELY started kicking ***. Best of all its much quieter.

I believe the problem with the original venturi was that I blocked off a lot of water flow, thus slowing the air draw to nothing. This mod reopened up the pump input, and allowed for a bigger venturi thus adding more air. The water level is set at the very very top of the body but not in the neck, and it overflowed while I was trying to take a pic. o.O

hounddog01 · 02/11/2007, 08:37 PM

Nice Mod. Looks like there are lots of bubbles in there now.

Kurt03 · 02/11/2007, 08:56 PM

is that normal air line tubing?

Maeda · 02/12/2007, 01:46 AM

yes.

BLockamon · 02/12/2007, 10:35 AM

Thus far the GG mod on my impellar isn't hitting on much. I'm probably going to switch to a mesh mod.

My main problem now is that 1) the water level in the skimmer (RPS-3000) isn't constant anymore and 2) the air draw drops from ~8-9 LPM to ~6 LPM every day or two. I flush the air line with water (which is draws in really well now for some reason), and it comes back only to drop again later.

I don't know if the water level fluctuation is from the air draw or variation in the feed from my tank overflow line, but I suspect the air.

Any suggestions on how to fix the rapid change in air draw? Prior to the GG mod, I had to flush the venturi maybe one a week; now it is almost daily.

RichConley · 02/12/2007, 10:41 AM

Blockamon, you need bigger airline, or you're going to keep having your venturi clog.

BLockamon · 02/12/2007, 05:48 PM

Rich, thanks. I'm looking into getting a spare venturi I can play with. Thinking of drilling out the current air barb for a 1/8" NPT and using an NPT x 1/4" tubing fitting. I suppose I'll need to add a short length of rigid airline to the NPT end and cut it at an angle to get the dP needed to draw air. Does that sound about right?

Thanks.

rleechb · 02/13/2007, 09:39 AM

I'm running an NW150, meshmodded and with the gate valve mod. I don't have a dwyer meter, so I'm not sure how much air I'm pulling. Does anyone think it's necessary to drill out the venturi or do any more modifications to the skimmer, or have I maxed it out?

hounddog01 · 02/13/2007, 09:50 AM

If it is working and pulling lots of gunk then you should be good to go.

rleechb · 02/13/2007, 10:00 AM

yeah, it's doing a really good job. I'm just one of those guys who likes to maximize performance. If there was a mod for my toilet, I'd probably spend a weekend doing it.

RichConley · 02/13/2007, 10:20 AM

Quote:

Originally posted by rleechb
yeah, it's doing a really good job. I'm just one of those guys who likes to maximize performance. If there was a mod for my toilet, I'd probably spend a weekend doing it.

There is a mod for your toilet, and I've done it.

At this point, you're gonna need to get a flowmeter to really go any further. You can get more air by going to larger airline, and changing the venturi, but its not always intuitive, and some things you'd think should increase air, dont.

rleechb · 02/13/2007, 10:27 AM

Quote:

Originally posted by RichConley
There is a mod for your toilet, and I've done it.

At this point, you're gonna need to get a flowmeter to really go any further. You can get more air by going to larger airline, and changing the venturi, but its not always intuitive, and some things you'd think should increase air, dont.

Looks like it's time to get a flowmeter (like I don't spend enough time on my tank as it is).

I've been considering doing a recirculation mod on my toilet, but I heard it was messy, and a crappy mod overall (pun intended).

SeaView · 02/13/2007, 02:07 PM

I have an NW-200

I have done the mesh mod ( 2 layers of enkamat) and expanded the venturi slightly and added solid airhose tubing. I can tell from visual id and the suction at the end of the air hose that in air flow is much greater and there are denser bubbles in the chamber. However, skimate is down and foam appears to just be hanging just over the lip of the collection cup but not falling. I have raised the water level tube and still not producing.

Could there be too much turbulence? Should I be lowering the level tube? Really want this skimmer to start earning it's keep.

hounddog01 · 02/13/2007, 04:35 PM

Just ordered a new prop to do the mesh mod on. If it does not work I can use the new prop.

klasiksb · 02/13/2007, 04:39 PM

Quote:

Originally posted by hounddog01
Just ordered a new prop to do the mesh mod on. If it does not work I can use the new prop.

Are you going to cut one row of pins off? Do you have a flowmeter?

Interested in your results because I was going to order another impeller to do the same. Just putting mesh on the stock impeller hasn't proven much better for me.

RichConley · 02/13/2007, 04:40 PM

SeaView, has your NW200 been recirced? Is it moving a LOT more water than it used to?

Mine moved too much water before I recirced it.

02/10/2007, 12:23 PM	#933
Avast Marine RC Sponsor Join Date: Feb 2006 Location: Northern VA Posts: 2,446	Sounds like you reduced water flow and thus reduced airflow as well. Since you already opened up the venturi, I would get a 1/8" mpt to 1/4" barb fitting and tap the venturi hole and put in the fitting, then connect your airline to that. __________________ Dan Don't rush art, you get bad art.

02/11/2007, 08:37 PM	#936
hounddog01 Registered Member Join Date: Dec 2003 Location: Bloomington, IL Posts: 1,045	Nice Mod. Looks like there are lots of bubbles in there now. __________________ Brad "The only true wisdom is in knowing you know nothing." - Socrates Current Tank Info: 180 gallon Acrylic, 65 gallon custom sump, Octopus Extreme 250, 150 LBS Marco Rock, 2-250 W Phoenix with 4 110 VHO supplement

02/12/2007, 10:41 AM	#940
RichConley Registered Member Join Date: Sep 2004 Location: Bostonian in Chicago going to DC Posts: 9,908	Blockamon, you need bigger airline, or you're going to keep having your venturi clog. __________________ NO TANKS!!!

02/13/2007, 09:50 AM	#943
hounddog01 Registered Member Join Date: Dec 2003 Location: Bloomington, IL Posts: 1,045	If it is working and pulling lots of gunk then you should be good to go. __________________ Brad "The only true wisdom is in knowing you know nothing." - Socrates Current Tank Info: 180 gallon Acrylic, 65 gallon custom sump, Octopus Extreme 250, 150 LBS Marco Rock, 2-250 W Phoenix with 4 110 VHO supplement

02/13/2007, 04:35 PM	#948
hounddog01 Registered Member Join Date: Dec 2003 Location: Bloomington, IL Posts: 1,045	Just ordered a new prop to do the mesh mod on. If it does not work I can use the new prop. __________________ Brad "The only true wisdom is in knowing you know nothing." - Socrates Current Tank Info: 180 gallon Acrylic, 65 gallon custom sump, Octopus Extreme 250, 150 LBS Marco Rock, 2-250 W Phoenix with 4 110 VHO supplement

02/09/2007, 09:20 AM	#926
coryjac0b Registered Member Join Date: Jan 2006 Location: Metairie, LA Posts: 823	is the gate valve mod needed if i plan on running the skimmer externally from my sump?

02/09/2007, 02:36 PM	#928
markywmson Registered Member Join Date: Feb 2006 Location: Bristol, CT Posts: 303	Quick question... I did the mesh-mod with 3 layers, seems to be working well so far. Those who have done it and had it running for awhile... how often (if ever) do you need to rinse/clean the mesh out? Thanks -Mark

02/09/2007, 04:40 PM	#929
Maeda Registered Member Join Date: Sep 2005 Posts: 251	I just got a NW150, and couldn't wait longer then a week before playing with it. so, I bored out my 90 degree elbow after the pump I removed one of the NW's and put 3 layers of GG on the impeller After this the pump looked like it was pushing way way way more water, so i decided to enlarge the venturi. I drilled through the stock plastic ridgid tube and jammed a 1/4" airline through (blocking off the wtock 'elbow' portion) so no it just goes straight down blocking off some of the water inlet. Now things don't seem to be working better... This just made my venturi very very VERY loud. Any thoughts?

02/10/2007, 09:53 AM	#932
Maeda Registered Member Join Date: Sep 2005 Posts: 251	I did do them one at a time, its just truncated for ease here. The real problem i'm having is that after I goofed with the venturi, I think it's not skimming as well..... and I was wondering why.

02/10/2007, 07:38 PM	#934
Maeda Registered Member Join Date: Sep 2005 Posts: 251	Ah, I guess I cut the water flow too much with that huge airline.. So for future skimmer mod endeavors, its not a good idea to cut water flow? I was thinking restricting the intake would force the pump to pull more air, drying out the mixture...

02/10/2007, 10:37 PM	#935
Maeda Registered Member Join Date: Sep 2005 Posts: 251	I was **ed off today. My original venturi mod didn't suck. Well it sucked but not air. SOOOOOOO I came up with a new venturi octopus mod. I bored out one hole, and then the 90 degree hole facing the pump. The bit was 'too large' and it broke through half the pipe wall. I then glued air line to what was left of the pipe wall and gently pulled it 90 degrees up to the silencer. My skimmer IMEDIATELY started kicking *. Best of all its much quieter. I believe the problem with the original venturi was that I blocked off a lot of water flow, thus slowing the air draw to nothing. This mod reopened up the pump input, and allowed for a bigger venturi thus adding more air. The water level is set at the very very top of the body but not in the neck, and it overflowed while I was trying to take a pic. o.O

02/11/2007, 08:56 PM	#937
Kurt03 Registered Member Join Date: Mar 2006 Location: Ohio Posts: 3,602	is that normal air line tubing?

02/12/2007, 01:46 AM	#938
Maeda Registered Member Join Date: Sep 2005 Posts: 251	yes.

02/12/2007, 10:35 AM	#939
BLockamon Registered Member Join Date: May 2005 Posts: 1,104	Thus far the GG mod on my impellar isn't hitting on much. I'm probably going to switch to a mesh mod. My main problem now is that 1) the water level in the skimmer (RPS-3000) isn't constant anymore and 2) the air draw drops from ~8-9 LPM to ~6 LPM every day or two. I flush the air line with water (which is draws in really well now for some reason), and it comes back only to drop again later. I don't know if the water level fluctuation is from the air draw or variation in the feed from my tank overflow line, but I suspect the air. Any suggestions on how to fix the rapid change in air draw? Prior to the GG mod, I had to flush the venturi maybe one a week; now it is almost daily.

02/12/2007, 05:48 PM	#941
BLockamon Registered Member Join Date: May 2005 Posts: 1,104	Rich, thanks. I'm looking into getting a spare venturi I can play with. Thinking of drilling out the current air barb for a 1/8" NPT and using an NPT x 1/4" tubing fitting. I suppose I'll need to add a short length of rigid airline to the NPT end and cut it at an angle to get the dP needed to draw air. Does that sound about right? Thanks.

02/13/2007, 09:39 AM	#942
rleechb Registered Member Join Date: Mar 2003 Location: Fremont, CA Posts: 2,684	I'm running an NW150, meshmodded and with the gate valve mod. I don't have a dwyer meter, so I'm not sure how much air I'm pulling. Does anyone think it's necessary to drill out the venturi or do any more modifications to the skimmer, or have I maxed it out?

02/13/2007, 10:00 AM	#944
rleechb Registered Member Join Date: Mar 2003 Location: Fremont, CA Posts: 2,684	yeah, it's doing a really good job. I'm just one of those guys who likes to maximize performance. If there was a mod for my toilet, I'd probably spend a weekend doing it.

02/13/2007, 02:07 PM	#947
SeaView Registered Member Join Date: Dec 2001 Location: LI/NY Posts: 586	I have an NW-200 I have done the mesh mod ( 2 layers of enkamat) and expanded the venturi slightly and added solid airhose tubing. I can tell from visual id and the suction at the end of the air hose that in air flow is much greater and there are denser bubbles in the chamber. However, skimate is down and foam appears to just be hanging just over the lip of the collection cup but not falling. I have raised the water level tube and still not producing. Could there be too much turbulence? Should I be lowering the level tube? Really want this skimmer to start earning it's keep.

02/13/2007, 04:40 PM	#950
RichConley Registered Member Join Date: Sep 2004 Location: Bostonian in Chicago going to DC Posts: 9,908	SeaView, has your NW200 been recirced? Is it moving a LOT more water than it used to? Mine moved too much water before I recirced it. __________________ NO TANKS!!!