Octo NW200 Step by Step to 40scfh
 

Ok, with the amount of info out there for the octo mods there's so much crap in the thread i wanted to just make a simple step by step. There's to much talk of the venturi and this and that. Its a very simple mod to do, will take all of an hour. I've been getting a large amount of email's about them here so i wanted to make a step by step so i can just link to this thread every time. Here's what you do. First take all the blades off the top nw to make it lighter. Starting point was 10scfh hooked up.

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC101-2-08.jpg[/IMG]

Second, use a dremel and a sanding bit to grind out the elbo as much as you can. But be careful or you will go through the other side. This is a huge restriction for the pump and output of the air. Heres mine boared out.Must boar out both ends.

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC91-2-07.jpg[/IMG]

Next get 4 layers of enkamat pf4, its on ebay, or pm sherm71(sorry man) and take 4 zip ties(very small ones) and cut the mesh exactly the same size as the impeller blades. Face the head of teh zip ties towards the volute cover, opposite impeller. Trim it so its not touching the sides or top of the volute cover.

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC81-2-08.jpg[/IMG]

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC71-2-08.jpg[/IMG]

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC61-2-08.jpg[/IMG]

Next is the simplest part there is. Take a dremel and the same grinding bit, and drill a hole on the male thread coming out of the volute cover. Do this as close as you can to the impeller casing without cutting it to close. Use a 1/4" od hose adapter from lowe's....etc. Take the hose adapter and cut a slit in it at the bottom, on two of the segments. Fact that towards the impeller. If you don't face the slit towards the impeller, it won't pull any air. Stick it down as far as it will go, and use super glue to bond it.

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC51-2-08.jpg[/IMG]

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC41-2-08.jpg[/IMG]

The next thing i faced was the riser tube was just to high. This skimmer is use to pulling 10scfh so it needs to be high. You are now at 35-40scfh so it will overflow the crap out of your skimmer. I cut nearly 4.5" off the riser tube so i can control the height of the water.

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC31-2-07.jpg[/IMG]

And here's what the 40scfh in teh octo 200 looks like. The second pic is me pointing to where the water line stops.

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC21-2-07.jpg[/IMG]

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/SWC11-2-07.jpg[/IMG]

I hope this simplified if for many of you and I hope it has answered many questions about the whole mod thing. This will work just fine for the nw150 as well. It should give you around 20-25scfh for the 150.

This mod puts you at 40scfh, 19lpm, or 1135lph air. This can handle a lightly stocked 283g tank, a med stocked 190 or heavily stocked 140g tank. The ratings are for water volume, so you have to look at actual volume, subtract sand, rock....etc. These are all imo ratings but i feel they are pretty safe.

This should run you about 10bux in supplies. The skimmer total with shipping 195+ 10 for the mods, a skimmer that will skim that large a tank for 205bux. It truly is the poor man's skimmer and easily the best value out there. I was going to recirc it, but i just don't know if its worth it at this point. I'm definately going to do a gate valve but that will pry be it.

Luke

Stand back from the things your taking pics of next time :D.. little blurry. Good info though!

I'll get some better pics in a couple days.

very nice....how about the recirc models...

I was just messin Luke, they're fine. People with this pump/set up should be able to tell what you were getting at.

luke33- What skimmer is this? Is that the new SWC xtreme skimmer?

Recirc you boar out the elbo add the same venturi, seal with superglue, then with cauk. Then do the same thing to the impeller. Youll most likely have to boar out the input as well. I was planning on doing the recirc to it, have the uniseal's and all but I don't think its going to make a huge change in performance.

Its just a regular old octo nw200 that i ordered from marinesolutionsinc for 179bux. Its the best budget skimmer out there you can get to perform like any high end skimmer out there imo.

Luke- don't you need to watch the power the pump is pulling so you don't burn it up???

I've done this mod so many times at around 60-65w i don't worry about it to much anymore. But if i had never done this before i would definately suggest a kill a watt.

thanks for this thread luke im going to bookmark this thread

think it might work on a 110 model also?

nice write up... I have a nw150, does both sides of the elbow need to be bored out??, one side seems to be pretty large, larger than a dremel sanding bit?? or is it??

I have 3 layers of mesh on my NW, does the 4th really make a difference??

I know you cut the top needles off the NW, but did you cut any of the back needles off?? or left them all on?

Would fishing line be better?? less weight?

Fishing line is less weight but it will not hold up over time IME. I just don't like using it. I use 4 very small zip ties that are 18lb test. 3 layers of mesh on the 150 is just fine. The input side of the recirc you may not need to boar out if its opened up enough. I left all the NW's on the back side. You could pop a few off if your worried about weight.

For the 110 i'm sure it will work but i wouldn't add more than 2 layers of mesh on it as its a much smaller pump.

Thanks Luke! I really appreciate the help. I have gone through that entire thread of mods, and holy moley it got out of hand!

2 more questions:

Do you have any clear pics of the "slits" you cut into the 1/4" OD hose adapter? Were you just using a dremel bit, or an exacto-knife?

Also, did you put any valves on the airline?

Are all the mods necessary or could I just do the mesh mod and get a smaller bump in performance?

I used a pvc cutter to make the slit. Here's a pic of a different pump i was modding but same thing. No air valve on the air line, i guess you could add one if you wanted too. Its very important that the slit faces the impeller and does not move. A slight turn will cost you alot of air or no air.

[IMG]http://i166.photobucket.com/albums/u88/lukewoehler/Venturi511-24-07.jpg[/IMG]

[QUOTE][i]<a href=showthread.php?s=&postid=11512025#post11512025 target=_blank>Originally posted</a> by axia55 [/i]
[B]Are all the mods necessary or could I just do the mesh mod and get a smaller bump in performance? [/B][/QUOTE]

You'll get a bump in performance with the mesh but the biggie's are the elbo and venturi. The meshwheel will give you a couple more but to really get the 35-40 mark you need to do all three.

I guess I will need a dremel to complete all three. Any recomendations on a reasonably priced model?

could you post come clearer pics of the elbow after it was dremeled and a picture of the tool you used to do it?

Its in my sump now. The elbo is just really restricted, very easy to see once you pick it up.

Any sort of bit like this works fine.

[url]http://www.lowes.com/lowes/lkn?action=productDetail&productId=94729-353-952&lpage=none[/url]

And any dremel like this will work. You should be able to pick one up for 25ish or as much as you would like to pay. If it has a cord it will be cheap, if its cordless more, but much sweeter!

[url]http://www.lowes.com/lowes/lkn?action=productDetail&productId=94788-353-7700&lpage=none[/url]

Trying to find a similar hose adapter at Lowes or Home Depot and this was the only thing even close -
[url]http://www.lowes.com/lowes/lkn?action=productDetail&productId=24861-104-A195/PB222N[/url]

Would that work or should I look for something more like the one you used?

I am also assuming this is what you connect the airline to once you are finished, correct?

Thats what i used....its just an older model of hose adapter. They will be right there or right next to them. Lowe's, ace, menards, HD all carry these guys for around 99cents. There hanging up in little bags in the plumbing dept

I just added the 4th layer of mesh, bored out the other side of the elbow and wow, it's already pulling better foam. Tested the pump after putting on the 4th layer of enkamat, 26watts now and .27 power factor, i dont know if thats a good number for power factor, is it?

26w sounds good, not sure about the power factor, doesn't sound bad to me though. Sounds good man.

well actually its running right at 38/39w, stock rating is 38w. And pf is at .41. Before it was tested in a bucket. Now, hooked up in the sump under 12 or 13 inches of water is how i'm getting these new numbers.