Octopus Skimmer Mods

[Bunkerbean]

So I had some observations after my mods were finished.

Last night my mess showed up. So I out a single layer of that on the impeller. On Sunday I bored out the venturi holes. On the right angle air way I bored out the entire channel through the bottom wall. Hope that makes sense.

So I turned it on and the foaming went nuts. Just a little background. I am in the process of setting up a 125 reef. I have tubs of LR with heaters and powerheads for the time being. Waiting on plumbing is a pain. Anyway so I set the skimmer up in one of the tubs. It is foaming like made. So I think nothing of it, go to bed since it was 11:30 anyway. Get up this morning and the collection is filled with clear water and bubbles are coming out the top. Does this mean I have to much air? Or is there something else going on?

[davidabrown66]

Originally posted by Bunkerbean
So I had some observations after my mods were finished.

Last night my mess showed up. So I out a single layer of that on the impeller. On Sunday I bored out the venturi holes. On the right angle air way I bored out the entire channel through the bottom wall. Hope that makes sense.

So I turned it on and the foaming went nuts. Just a little background. I am in the process of setting up a 125 reef. I have tubs of LR with heaters and powerheads for the time being. Waiting on plumbing is a pain. Anyway so I set the skimmer up in one of the tubs. It is foaming like made. So I think nothing of it, go to bed since it was 11:30 anyway. Get up this morning and the collection is filled with clear water and bubbles are coming out the top. Does this mean I have to much air? Or is there something else going on?

It sounds like you're curing LR. Your skimmer will go nuts from all the die off if that's the case. I would dial it back and open up the gate valve, and if that doesn't work, I would get an air valve for the venturi hose, and dial it back a little.

[davidabrown66]

Tried the hose gasket, and it lowered my wattage without impacting air, but I doesn't seem to skim as well so I backed it out.

[Bunkerbean]

When you say dial it back and open the gate vavle what do you mean. I didn't put one on. Should I have?

Yeah I guess I am curring. The water has slowly deterioated. It has taken longer than expected getting this system set up.

[squin]

Originally posted by davidabrown66
Tried the hose gasket, and it lowered my wattage without impacting air, but I doesn't seem to skim as well so I backed it out.

That's good to know. How did it impact your skimming?

[davidabrown66]

Originally posted by squin
That's good to know. How did it impact your skimming?

Hard to describe, and may be just in my head, but it didn't seem to be circulating as fast. My wattage fell to 52 watts from 70. I then tried a thicker gasket so less ID, and the pump wattage fell to 40 watts and 15 SCFH from 25.

[davidabrown66]

Originally posted by Bunkerbean
When you say dial it back and open the gate vavle what do you mean. I didn't put one on. Should I have?

Yeah I guess I am curring. The water has slowly deterioated. It has taken longer than expected getting this system set up.

Sorry, I was thinking you had a nw-150 with the gate valve mod.

[Bunkerbean]

No mine was just the NW-150. I did the mess, and bored the nipple out.

[squin]

Originally posted by davidabrown66
Hard to describe, and may be just in my head, but it didn't seem to be circulating as fast. My wattage fell to 52 watts from 70. I then tried a thicker gasket so less ID, and the pump wattage fell to 40 watts and 15 SCFH from 25.

That makes sense as the pump was not moving as much water, but the same amount of air with the thinner washer. Sounds like the thicker washer was to restrictive without enough water flow to pull the full volume of air.

Your results support the assumption that we can restrict the water flow and wattage while maintaining airflow to a point. Now the trick is finding the optimum point. I need to try a thicker washer to see if I can get my flow down further and still pull max. air.

The turbulence in my skimmer decreased as well, but I'm getting a much better (drier) foam now. I also noticed the bottom of the bubble layer in the skimmer tower moved from about 2 inches off the bottom to about 5 inches off the bottom. I think I read in earlier posts that less turbulence and more air was a good thing. Thoughts?

Thanks for playing along!

[hounddog01]

Originally posted by Bunkerbean
So I had some observations after my mods were finished.

Last night my mess showed up. So I out a single layer of that on the impeller. On Sunday I bored out the venturi holes. On the right angle air way I bored out the entire channel through the bottom wall. Hope that makes sense.

So I turned it on and the foaming went nuts. Just a little background. I am in the process of setting up a 125 reef. I have tubs of LR with heaters and powerheads for the time being. Waiting on plumbing is a pain. Anyway so I set the skimmer up in one of the tubs. It is foaming like made. So I think nothing of it, go to bed since it was 11:30 anyway. Get up this morning and the collection is filled with clear water and bubbles are coming out the top. Does this mean I have to much air? Or is there something else going on?

Is your skimmer new. It took 2 weeks for mine to quit this then another month before it started working consistantly. after 4 months this thing is a monster. Skims dark green to black and I can adjust it very easily.

[Bunkerbean]

Actually it is brand new. It was skimming dark green before the mod.

[tikalize]

Thanks Outy

[reefez]

Is your skimmer new. It took 2 weeks for mine to quit this then another month before it started working consistantly. after 4 months this thing is a monster. Skims dark green to black and I can adjust it very easily.

Same story here. I had major issues with mine in the very beginning. It flooded my stand twice and in the process fried a Iwaki 40 rlt. Be patient with it. My 3000 was very touchy and hard to dial in for the first couple weeks. It is now doing what I had hoped for all along. I just cleaned the collection cup last night, and it is allready 3/4 full in 24 hrs.

[davidabrown66]

Originally posted by reefez
Same story here. I had major issues with mine in the very beginning. It flooded my stand twice and in the process fried a Iwaki 40 rlt. Be patient with it. My 3000 was very touchy and hard to dial in for the first couple weeks. It is now doing what I had hoped for all along. I just cleaned the collection cup last night, and it is allready 3/4 full in 24 hrs.

Mine has been just the opposite. The DNW-200 sucks (not in a good way) right out of the box without mods (6-7 SCFH), and it just sat there like a giant tube of water with a fizzy stone attached until I did enough of the mods to get at least 15 SCFH. I've had it for a couple of months now, and I've only recently started to get daily 1/4 cup of medium colored green tea.

As a contrast, my Aqua C EV-180 pulled out the same amount using a filter sock, but much darker, and I thought it was under performing for what I wanted to do in the future. This may also be b/c I was pulling more of the raw water from the sump with the EV. Now, I'm using a filter sock again with the ph in the sock and pushing return water to the skimmer. Since this power head only delivers a small amount of water compared to other types of skimmer, it seems like the skimmer is only getting a small fraction of what actually needs to be skimmed.

I'd like to section off my sump in a way that I could isolate the worst part of the return water for skimmer processing. My thinking is that I would have this part of the sump not over flow into the rest of the area, but drill the bottom of the partition or leave the bottom of the partition open so only the worst part settles on the top and have the skimmer process that water.

How do others have theirs set up?

I can't use my return for delivering water b/c of the way my returns are set up. I have water coming from the main tank, then under the house, then into the garage, then up from the floor using 2" PVC. I tried to tee the line and use that to deliver water, but it just girgled in, and wasn't consistent. I'm sure I could redo the plumbing so this works better, but for now I just want to get this thing performing at its best.

As an example, a couple of days ago I mixed up a batch of zoo plankton and phyto plus some other stuff to feed over the course of several days. I went to feed the other AM without the lights on in the dark, and realized I had fed almost the entire contents

I decided to see if this would be a good test to see if the skimmer would pull out more gunk over the next 24 hours having done this, and it didn't.

So, we're not there yet, but I have two more stock venturi's coming this week so I'll see if I can mod one of them to 30 SCFH+
and mod my sump this weekend so my skimmer grabs the worst of the water coming from the tank.

Cheers

[squin]

Originally posted by davidabrown66
So, we're not there yet, but I have two more stock venturi's coming this week so I'll see if I can mod one of them to 30 SCFH+
and mod my sump this weekend so my skimmer grabs the worst of the water coming from the tank.

Cheers

Where did you find venturi's? My source has not shipped the correct venturi after 3 attempts.

[davidabrown66]

Squin, pm sent

[outy]

can someone give me a guess on scfh on the octo 3000 pump, with 3 layers enkamat and 1 needlewheel busted off and the venturi drilled out to 1/4 id tubing id

[davidabrown66]

Originally posted by outy
can someone give me a guess on scfh on the octo 3000 pump, with 3 layers enkamat and 1 needlewheel busted off and the venturi drilled out to 1/4 id tubing id

Hard to say, do you have in internal or external skimmer?

The internal skimmers seem to have a higher SCFH right out of the box. If this is an external, I would guess 15-25

[medic29]

I have mine in sump with 10 inches of water and I'm consistently pulling 20. The mods I've done is remove the first needle wheel, then I finished breaking off all but 4 of the needles on the rear needle wheel. It wasn't intentional to break these off initially, but I broke 2 or 3 off trying to get the front needle wheel off. I had a hard time getting it to work and figured out that the missing needles was throwing the impeller out of balance. So I tried breaking off additional needles until I only had 4 left each at 90 degree angle to the others. Now that the impeller is balanced, and I attached the enkmat, I have no problems with the skimmer starting; before I did this, I had trouble getting it to start. I also drilled out the nipple on the venturi and glued in a 1/4 inch hose flange and attached a 1/4" ID hose to it. I drilled out the 90 degree part of the venturi as well.

I have casted a few more venturis and have played with them some. I even casted one where I can drill out the inside of the venturi to the diameter I want. I'm not sure if I want it larger than the stock venturi or smaller. I was thinking smaller, which would increase the velocity of the water being pulled through and thus should increase the venturi (suction) action and thus pull more air; but, I'm sure this theory will work. I guess I could try it and check the results, then cast another one and drill it larger and check the results.

Any thoughts??

[davidabrown66]

Originally posted by medic29
I have mine in sump with 10 inches of water and I'm consistently pulling 20. The mods I've done is remove the first needle wheel, then I finished breaking off all but 4 of the needles on the rear needle wheel. It wasn't intentional to break these off initially, but I broke 2 or 3 off trying to get the front needle wheel off. I had a hard time getting it to work and figured out that the missing needles was throwing the impeller out of balance. So I tried breaking off additional needles until I only had 4 left each at 90 degree angle to the others. Now that the impeller is balanced, and I attached the enkmat, I have no problems with the skimmer starting; before I did this, I had trouble getting it to start. I also drilled out the nipple on the venturi and glued in a 1/4 inch hose flange and attached a 1/4" ID hose to it. I drilled out the 90 degree part of the venturi as well.

I have casted a few more venturis and have played with them some. I even casted one where I can drill out the inside of the venturi to the diameter I want. I'm not sure if I want it larger than the stock venturi or smaller. I was thinking smaller, which would increase the velocity of the water being pulled through and thus should increase the venturi (suction) action and thus pull more air; but, I'm sure this theory will work. I guess I could try it and check the results, then cast another one and drill it larger and check the results.

Any thoughts??

I've tried many variations, and the best method i've heard of was from Roland Jacques in pulling 40 SCFH on a NW200 making his own venturi out of a 1" pvc coupler. Here's a pic:

http://reefcentral.com/forums/showth...5&pagenumber=5

[outy]

ive got the dual pump 250 recirc octopus.

in rolands pics he has the stock venturi modded the same way as mine, the 1" coupler is just for plumbling either recirc or for getting raw water to the pump itself.

ive read almost every page and i havent seen anyone posting bad results from the recircs, only good

the only negative on the way they designed the octo 250 recirc is that the pumps sit flat on the bottom [the 300 doesnt] so there is higher head pressure, but with the positive that your not having to lift the water collum with the pump it will be interesting.

ive ordered my air meter this morning and ive left 1 pump stock to get definitive results on each mod.

the skimmer has been up for 4 days and with the o-ring mod venturi and 2 layers of GG on the stock impeller of 1 pump its already pulling some decent foam.

[Bunkerbean]

I got to thinking a little more about my mesh mod. Since I have the 2000 pump, my needlewheel came with only 2 rows. I wonder if I should clip off the first one and double mesh the last one. Not sure if that would be beneficial or not.

[davidabrown66]

Originally posted by outy
ive got the dual pump 250 recirc octopus.

in rolands pics he has the stock venturi modded the same way as mine, the 1" coupler is just for plumbling either recirc or for getting raw water to the pump itself.

ive read almost every page and i havent seen anyone posting bad results from the recircs, only good

the only negative on the way they designed the octo 250 recirc is that the pumps sit flat on the bottom [the 300 doesnt] so there is higher head pressure, but with the positive that your not having to lift the water collum with the pump it will be interesting.

ive ordered my air meter this morning and ive left 1 pump stock to get definitive results on each mod.

the skimmer has been up for 4 days and with the o-ring mod venturi and 2 layers of GG on the stock impeller of 1 pump its already pulling some decent foam.

How did you overcome the metric to standard pvc fitting, and why would go to the trouble of using a 1" coupler if not to make your own venturi?

[davidabrown66]

Originally posted by outy
ive got the dual pump 250 recirc octopus.

in rolands pics he has the stock venturi modded the same way as mine, the 1" coupler is just for plumbling either recirc or for getting raw water to the pump itself.

ive read almost every page and i havent seen anyone posting bad results from the recircs, only good

the only negative on the way they designed the octo 250 recirc is that the pumps sit flat on the bottom [the 300 doesnt] so there is higher head pressure, but with the positive that your not having to lift the water collum with the pump it will be interesting.

ive ordered my air meter this morning and ive left 1 pump stock to get definitive results on each mod.

I don't think rolands mod was intended for recirc models b/c on the recirc models the stock venturi has two sets of threads.

the skimmer has been up for 4 days and with the o-ring mod venturi and 2 layers of GG on the stock impeller of 1 pump its already pulling some decent foam.

[outy]

i havnt had to overcome metric to standard yet [i havnt modded that much]

look at rolands design you can still see the stock venturi thats modded. the 1" you see is more then likely just to plumb raw water to the pump