Octopus Skimmer Mods

[davidabrown66]

Originally posted by JCTewks
Sorry david...i think i misread your post...are you using 1/8, 0r 3/8 line?? my meter has a 3/8" threaded input on it, i think i'm confused. :l

It is confusing how these barbs are labeled. Essentially, the barbed end OD is 3/8" and the OD of the threads are 3/8". The ID of the barb is just slightly less than the OD of RO tubing (1/4"). I've taken a 1/4" drill bit and reamed out the barb for both the venturi and the meter so if anything it's too large of an ID. It is performing relatively well though now that I've cut the mesh the size of the old impeller and added a layer of GG. I'm right about 28 SCFH.

I did however take my Gen-x 4100 pump (that will probably replace my OTP-3000) to BR this weekend and had Skimmerwhisperer do the mesh and GG on it b/c I could'nt get it to work on the ER pinwheel pump and be stable. He finished the mod while showing me the areas that were giving me the problems. We tested that pump and it gave me 30 SCFH without the input/output plumbing which was pretty good. Not sure yet if I'm going to go all the way and swap this one out for OTP yet, b/c it seems like a pretty noisy pump, and there's no going back to the OTP once I start, b/c I'm hacking off the output plumbing to be used with the Gen-x. I guess I was hoping for a clear winner which would have been Gen-x if it'd given me 35+ SCFH.

More testing will tell if it's worth it. Right now, Gen-x has the nod as far as air to water ratio = less turbulance.

[outy]

less wattage to doesnt it?

[JCTewks]

david,

Are you using RO tube as your air line, or actual 3/8 ID tube? If you are using the RO tubing you only have an ID of about 1/8"
I'm going to post an overview of the mods I've done and you'll see my venturi using 1/4" ID tubing.

[JCTewks]

Well, here is a rough overview with pic's of the mods I've done to my DNW110 with the OTP1000 pump that will pull 20SCFH.

Here is the Venturi....you can see that I bored out the 90 using a small sanding drum on the dremel and Drilled through the existing air intake and put a 1/4" ID tubing connector in using super glue.


Bad picture, but the tubing adapter goes all the way to the other side of the venturi. I tried it with it only about half way through and the air draw was not as good as with it all the way across.



Here is where I smoothed out the exit of the volute and removed most of the little raised ridge around the inside of the volute.


The little bot of a ridge you see there is only about 1/16" wide. all of the material below that was removed. You don't have to leave that ridge there, it's just that my sanding drum was a little too short and I got a little lazy.

[JCTewks]

And, here is the impeller. Notice the gutter guard hplding the mesh down tight.


and the mesh and gutter guard on the back side of the impeller.

This impeller has one of the NW's still on it, although I did flip it over so that the teeth were pointing down. The mesh and GG was all sewn on using 10# test fishing line.


I also removed just a little bit of material from the face of the volute cover, and widened the insede of the inlet just a bit.




I couldn't get any good pistures of it, but I also opened up all of the plumbing on the skimmer body with the grinding wheel on the dremel, and drilled a few small holes in the tee on the water feed line.

Here is the finished skimmer running on the tank.



with all of these mods it got me to 20SCFH using 32 watts. 20SCFH is way too much air for that little 2.5" neck, so I added the 18" neck extension. Even with the extra neck, I still had to back off the air to around 15SCFH.

Feel free to ask any questions, I'll try and answer as best I can.

[outy]

id of ro/di is 3/16 with the rite mesh and porting the volute will get you mid 40,s scfh on a 3000 per roland j

[impur]

Well i removed my venturi and added a slightly larger ID tubing, but my scfh plummeted to about 10 from the previous 23scfh. I tried several other types of tubing, even tried the old one but couldn't get it back to the 23scfh. I ended up with a small piece of hard airline tubing inserted as close to the impeller as i could get. This gave me 19-20scfh, so i said screw it close enough and didn't touch it after that.

[davidabrown66]

Originally posted by outy
less wattage to doesnt it?

Strangley no. It's rated at 70 Watts. When I run it without air with mesh it reads about 85 watts, with air it reads about 45 watts so something seems wrong with my gen-x mod. I'm not getting 30 SCFH anymore either. I tried to trim the edges of the mesh that were catching on the volute edge, and that dropped my #'s down to 25 or so SCFH, and then I tried taking out the restrictions in the pump output and that dropped my #'s to 20 SCFH. I then added another layer of mesh, and that didn't do anything. I think I was having more fun with the OTP-3000.

Anyway, I have another Gen-x coming, this time with a needle wheel instead of the ER pinwheel so I can mesh it like the OTP. I'm just trying to run both mods in parallel to see which one will come out on top.

[davidabrown66]

Originally posted by JCTewks
david,

Are you using RO tube as your air line, or actual 3/8 ID tube? If you are using the RO tubing you only have an ID of about 1/8"
I'm going to post an overview of the mods I've done and you'll see my venturi using 1/4" ID tubing.

I'm using 3/8" tubing. Your pics are awesome!!!!! I think I'll try the GG on the top as well. Also, I see I can do a little more volute work on the OTP. The Gen-x has a smaller volute so no modding there.

[JCTewks]

Originally posted by davidabrown66
I'm using 3/8" tubing. Your pics are awesome!!!!! I think I'll try the GG on the top as well, and do the wireties like you have them as well. Also, I see I can do a little more volute work on the OTP. The Gen-x has a smaller volute so no modding there.

If you start removing material from the volute cover....be very careful and go slow. you can only remove about 1/16" or a little less before you go through the plastic.

[davidabrown66]

Originally posted by JCTewks
Well, here is a rough overview with pic's of the mods I've done to my DNW110 with the OTP1000 pump that will pull 20SCFH.

Here is the Venturi....you can see that I bored out the 90 using a small sanding drum on the dremel and Drilled through the existing air intake and put a 1/4" ID tubing connector in using super glue.


Bad picture, but the tubing adapter goes all the way to the other side of the venturi. I tried it with it only about half way through and the air draw was not as good as with it all the way across.



Here is where I smoothed out the exit of the volute and removed most of the little raised ridge around the inside of the volute.


The little bot of a ridge you see there is only about 1/16" wide. all of the material below that was removed. You don't have to leave that ridge there, it's just that my sanding drum was a little too short and I got a little lazy.

It looks like you bored out the venturi end more than the opposite end of the 90, is that right? I've tried going all the way into the waterway with the RO tubing, and that didn't seem to help. If anything it caused the wattage to drop below the rated 65 watts. I was using the larger RO tubing though, not the 1/4" but the 3/8" i think it was. I even went as far as to insert the line, and start the skimmer then while it was going I tried moving the line in and out of the waterway to see what would happen. I should try that again with 1/4" to see what happens. Also, when you cut the airline at an angle, is the angle of the opening facing away from the waters direction so it doesn't push water into the air line?

Thanks again for pics, it's really helping a lot. I was ready to give up again last night for the 10 time, but now I have renewed faith.

[JCTewks]

Yes, the open side of the angle is facing the pump, so that is drawing air, not having water pushed into it.

Don't give up, you never reallylearn if you don't fail from time to time. It's pron something really simple you've overlooked that is keeping your air down.

[charlesjordanjr]

I did the mesh mod - without taking off the needles. I just added 2 layers on top of the needles. I also added a second 1/4" hole in the veturi. I just drilled a hole at 90 degrees and inserted typical airline hose. I don't have a meter, but I can tell you by the noise, it is pulling in MUCH more air. I noticed the difference even before I added the 2nd venturi hole. I love it!!

I would like to thank you guys for being brave enough to be the guinea pigs and test the mods on your own equipment. Thanks!

-Chuck

[charlesjordanjr]

Oh, I also bought an extra impeller to experiment with. On that one, I will be taking off the 1st row of pins (needles?).

This experimental impeller has the newer and smaller diameter wheels. Should I make the mesh the same size as the old impeller? Just curious.

-Chuck

[JCTewks]

I made my mesh as big as it could without rubbing the sides of the volute.

[davidabrown66]

Originally posted by JCTewks
I made my mesh as big as it could without rubbing the sides of the volute.

I did the same thing, but watch out for problems trying to start your pump, and for wattage draw. You're essentially overdriving these pumps and this could easily jump your wattage to 95+ watts.

[JCTewks]

with my setup on the pump i'm at 32 watts/20SCFH on my OTP1000. the pump is labeled at 18 watts, but even out of the box it was doing 30....so i figure a 2 watt gain for an extra 16 SCFh isn't too bad

[davidabrown66]

The OTP-3000 can be an energy hog depending on the mods.

I took your advise and did some more mod'ing to the volute including the 1/16" edge and water output, etc. This dropped my wattage about 10W, and it increased my air. I'm finally pushing 32 SCFH, and I'm able to do that at 78 watts now.

So the mesh will increase the watts used, also increasing the diameter of the mesh, which in turn increasing water flow and air, will increase wattage. Opening up the volute which is a restriction on the output, decreases the energy used to move a given amount of water so that will reduce the watts.

Thanks for the advice!

[mr evolution]

What are some of you guys using for a collection container?

I'm debating if I should spend a $100 bucks on a acrylic piece that has a ping pong ball as an air valve.

[impur]

I just clean mine every week when i do a WC. I would just use a milk jug or something if i did use a drain.

[outy]

i wouldnt spend any cash.

i use a 2G container that used to have salt in it. oceanic i think.

if thats not good enough you can make something cheap that will work and still look nice

[davidabrown66]

Originally posted by mr evolution
What are some of you guys using for a collection container?

I'm debating if I should spend a $100 bucks on a acrylic piece that has a ping pong ball as an air valve.

Sounds like a lot of $$ for a product you could probably make. Do you really need something that would cut your skimmate if the container were to become full? I mean, do you have consistent skimmate per day or does it overflow sometimes with a lighter skimmate and other times nothing at all?

I have a 1 gal juice container that I empty once a week, but it's only 1/8 full with dark skimmate. So it depends, if you're worried about inconsistent skimming then this is the product that one would buy, but I would not buy one unless I'd done all the other things that would give me more consistent skimmate like adding a baffle in my sump to give me a consistent water level for example, or the elbow mod if this is on a Octopus skimmer, etc.

I hate throwing $$$ at a problem without knowing more.

[Kurt03]

would be easy to DIY the ping pong ball shut off anyways wouldnt it?
Need a locking air tight lid on the skimmer as well or it wont work anyways. Ive been thinking about making one of these, just not sure the best way to make my lid airtight and locking on there. its a nw200

[niteshado]

Hi: I tried the AquaC large container since I had some problems with overflowing. It did NOT work for the OCT recirc 150 I had. IT filled up then leaked from the cup on the skimmer body. definitely not s helpful tool. I use an old 1 quart vase for out put now.

Larry

[StupidsReef]

I have the ddnw 300 recir octopuss and for the collection container I drain it into a 5 gallon bucket ( a corallife salt bucket) with the lid on it. I cut a hole in the lid to match the size of the tube and then used aquarium sealant to seal it off. I bump it once a week to see how full it is. You buy the salt and find a use for the container, plus my wife said if she could smell the oder of skim-mate I was a dead man. She can't smell it and it cost me $1.98 for the tude of sealant.