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calvin415
07-09-2008, 03:09 PM
Got some questions, I've talked with Russ about this for some length, but curious if anyone has seen this done, or has a thought I might be missing.

I'm considering the Octopus DNW-200 Recirc skimmer, and they recommend a feed pump pushing 1-1.5 x tank volume but rate the skimmer for a 400g tank.

Does my logic check out?
Since it's rated for a 400g tank does that mean it can handle 400-600 gph flowing through it? I mean, tank size shouldn't dictate skimmer capacity, if the skimmer was put on a 55g tank should it only get 55-75 gph fed through it? Most non-recirc skimmers have pumps pushing 400-800 GPH through the skimmer and this skimmer has an 800 GPH recirc pump.

I plan on running only a 500 gph return pump resulting in a 500 gph overflow rate and I want to divert the overflow directly into the skimmer. So with 500 GPH feeding the skimmer the water should be cycled 1.6x in the skimmer chamber...

Anyone have some thoughts on the matter?

Anyone ever seen this done?

racer69
07-09-2008, 03:42 PM
I think that would work great Eric, that is if you are leaving the pump on and then diverting the extra 500 to the skimmer also. If you are planning on only using the overflow volume of 500 gph, I would think you should supplement another pump between 300-500 gph. This would be very efficient since you would actually be double skimming.

calvin415
07-09-2008, 05:56 PM
No what I mean is the return pump from the sump to the tank will be 500 GPH which means the overflow from the tank and to the sump will also be 500 GPH. But instead of having it just dump into the sump, I'll have it dump directly into the skimmer so 100% of the water will travel through the skimmer before continuing on through the fuge and the return pump for another cycle. Make sense?

Because the pump on the skimmer is a recirc pump at 800 GPH that means the water from the tank will be skimmed 1.6 times before it leaves the skimmer.

Russ did bring up one point and that is, having the 800 GPH from the skimmer pump + 500 GPH from the overflow would be 1300 GPH traveling through a skimmer with an 8" diameter body. Wondering if that would be too turbulent? While the skimmer isn't as large as some others, my thought is if they can put a Dart (3600 GPH) on a skimmer then this should still work... I'd just do a mesh mod on the needle wheel to pull more air.

calvin415
07-09-2008, 06:23 PM
Dude on RC reminded me Iwill not be able to get 100% of your water skimmed because of large bubbles from the overflow getting into the skimmer...

My solution:

I plan on having a dual drain setup (1 main 1 backup), I'll valve the main back just enough to allow the back up handle a trickle to ensure the flow into the skimmer is bubble free. Maybe 95%-99% skimmed. Anything else I'm forgetting?

racer69
07-09-2008, 06:29 PM
That sounds like a very good plan. You should have some really clean water and you shouldn't have to use filter socks which are a pain in the a.

calvin415
07-09-2008, 06:30 PM
Well crap... :(


by spongebobby
I used to use that exact skimmer and about 250 gph is all it would handle. If you put to much flow in it you will overflow the skimmer. A MJ1200 worked great for me on a 120.

Although the skimmer had a hard time keeping up with a heavily stocked 120. It did work OK. I had to do water changes every week to keep the trates down. I would assume a heavily stocked 140 would be about the same. It definately can't handle 400 gal. tank, even modded.

racer69
07-09-2008, 06:35 PM
That sux. Looks like you may need to look for a different skimmer.

calvin415
07-09-2008, 06:40 PM
Yeah, I thought I finally had the skimmer I wanted. :( What really sucks is I have a limited footprint. Space under the tank is about 11.5" wide so with 3/4" for acrylic that leaves me about a 10x??? footprint for a skimmer. :(

Murfman
07-09-2008, 06:53 PM
E, what I found with my skimmer is that if I have too much return going back to the tank, It pushes the bubble column out and I get poor skimming. Put a ball valve or gate valve on the line from the return to the skimmer so you can control the input.

calvin415
07-09-2008, 07:08 PM
Hmmmmm, Anyone have an idea? Octopus skimmers seem to be the highest rated skimmers with the slimest footprint:

This will fit, but only rated at 160g
http://www.aquacave.com/octopus-extreme-160-br-protein-skimmer-br-by-coralvue-2199.html

There are two recircs that will fit, but same issue as before, I can't put more than 250 gph through the skimmer...

http://www.aquacave.com/octopus-dnw-200-recirculatingbr-protein-skimmer-985.html

http://www.aquacave.com/octopus-extreme-160-br-protein-skimmer-br-by-coralvue-2199.html

Should I say screw it and just dump 250gph through it and call it good?

Murfman
07-09-2008, 07:09 PM
What is your bio load going to be like?

Murfman
07-09-2008, 07:17 PM
I also split the return, using a T, so that I have some unfiltered water entering my sump/fuge. You could do that to keep your return rate constant.

calvin415
07-09-2008, 07:20 PM
Bio load will be high... It's only 140g's but because of the length it will really be full.

racer69
07-09-2008, 09:06 PM
With your foot print restrictions I think you are going to have some blow by and not be able to run 100% of the water through the skimmer. I think with your attention to husbandry everything will be fine. On another note, how tall can the skimmer be? You should be able to run more water through a taller skimmer and keep a small foot print.

calvin415
07-09-2008, 09:36 PM
I can do 30" tall...

calvin415
07-10-2008, 09:24 AM
Well I did some measuring and thinking and if I raise the sump off the concrete and build a floor so I can build a sump across the supports, I think I could get up to 15" wide... Provided I can get this additional space what are some recommendations on skimmers, the Octopus extreme has really caught my eye (same as the MSX) and the ATI looks sweet, but I've heard they are a waste of money and to get the MSX/Octo Extreme... Or should I just save the money and get another ASM?

Anyone been following the latest skimmers? I haven't. :(

racer69
07-10-2008, 11:41 AM
I personally think the Octopus line is a very good line. I haven't used one but know of others that have and they seem to really like them. They are made by the same company that made ASM.

calvin415
07-10-2008, 12:30 PM
Well, I think I found the skimmer I'm going to get (if I can find one at a fair price)...

http://www.aquacave.com/images/ps-sq-rl200_1_xl.jpg
ReeFlo Orca 200

* Watt Draw: 95 watts
* System Capability (gallons): 100 - 400
* Air Flow: 1,500 liters per hour
* Recommended Water Flow: 300-600 gph
* Footprint: 14.5" x 17"
* Diameter: 8"
* Height: 26"

racer69
07-10-2008, 01:10 PM
That looks like a cool skimmer. Are you still going to make it recirc, or is that what that nipple is for?

calvin415
07-10-2008, 01:33 PM
It is a recirc, the smaller nip is for the venturi, the larger one is for the feed... Supposed to take 300-600 GPH feed.

Thurge
07-10-2008, 02:14 PM
Todd said nipple.

calvin415
07-10-2008, 02:36 PM
Lol!

calvin415
07-10-2008, 07:37 PM
Crap! Well the Reeflo has a footprint of 16x16 and I only have 17.5x14.5 due to the studs... :(

http://i6.photobucket.com/albums/y242/calvin415/Ultimate%20Nano%20Projects/TopDown.jpg

Any ideas? Should I just say screw it and get something that isn't a recirc?

racer69
07-10-2008, 07:53 PM
Any ideas? Should I just say screw it and get something that isn't a recirc?

Not until you have exhausted all your options.:thumbsup:

calvin415
07-10-2008, 08:05 PM
Guess that means I'll be building my first skimmer... If I build it square that should help fight turbulence right?

racer69
07-10-2008, 08:10 PM
I was wondering when yu were going to come up with that idea. I think square will cut down on the turbulence, but what are you going to use for the cup and throat?

aquaman2000
07-10-2008, 08:11 PM
Or just put on a mechanical filter and a regular skimmer.

calvin415
07-10-2008, 08:17 PM
Good question Todd... Guess it's time to shop.


No way, I hate filter socks!

aquaman2000
07-10-2008, 08:22 PM
LOL..... there are tons of plans all over the net.....

aquaman2000
07-10-2008, 08:23 PM
http://www.google.com/search?hl=en&client=safari&rls=en-us&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=diy+recirculating+protein+skimmers&spell=1

Huhhhhh
07-10-2008, 08:32 PM
Crap! Well the Reeflo has a footprint of 16x16 and I only have 17.5x14.5 due to the studs... :(

Any ideas? Should I just say screw it and get something that isn't a recirc?

Hey Eric it looks like you can replumb that setup with some straight pipe and reduce that foot print into a narrower but longer footprint, it should fit inbetween teh studs that way I think.

calvin415
07-10-2008, 08:47 PM
Maybe Tim, I wish I could see one in person... :( Anyone know of one locally?

Huhhhhh
07-10-2008, 09:23 PM
I'll bet they have one at their facility here in town. Try and give them a call and ask if you could come see one or if they could pumb one for you that way for your application. Let them know you're a part of the club and you apreciate them as a sponsor and I'm sure they'll work with you.

calvin415
07-10-2008, 09:46 PM
Darn Tim, now I'm torn because I'm really thinking about building my own square version... :D

Reefkoi
07-10-2008, 09:54 PM
hmmm if square skimmers work why don't we see the high end skimmer guys building them? I don't know anything so I'm looking at it from a consumer point of view.
C

Murfman
07-10-2008, 10:19 PM
C'mon E, pony up the $ and get a Bubble King!!!!

calvin415
07-10-2008, 10:23 PM
hmmm if square skimmers work why don't we see the high end skimmer guys building them? I don't know anything so I'm looking at it from a consumer point of view.
C

Because Round is quicker and lots more pretty. :D


C'mon E, pony up the $ and get a Bubble King!!!!

Yeah right... I told Rachel I was going to get a Reeflo and she just about hit me. ;) If it's under a grand she is probably going to be okay, but BK's don't know without a comma. :D

calvin415
07-10-2008, 10:23 PM
Here's a sketch of what I'm thinking... Center diffuser would be 4", but I may consider going larger...

http://i6.photobucket.com/albums/y242/calvin415/Ultimate%20Nano%20Projects/SkimmerClone.jpg

calvin415
07-11-2008, 03:19 PM
Made some changes to fit my needs instead. It has a footprint of 11x17 which will fit directly on the cement, so no more need to build it up. Only real expense IMO will be the 6" acrylic tube for the riser, and modifying my dart pump to a needle wheel... Are the wheels easy to change out on a dart? I haven't taken mine apart yet.

http://i6.photobucket.com/albums/y242/calvin415/Ultimate%20Nano%20Projects/SkimmerClone2.jpg

calvin415
07-11-2008, 04:23 PM
Square will be a ton cheaper than tube, especially since it's tough to find it by the foot and not pay a forture for it... Anyone think I should spend the dough on tube? Anyone else want one to help lower the cost per unit?

racer69
07-11-2008, 08:47 PM
Dude, I think you should make the second one and try it. Even if it doesn't work the way you want, it won't be as expensive as buying an excellent name brand. And if it works you save, and if it doesn't, well you bit the bullet.

calvin415
07-11-2008, 09:42 PM
Thanks for your support bud! I'm going to do some test cones tomorrow and likely build a smaller prototype if anyone needs a nano skimmer.

Huhhhhh
07-11-2008, 10:59 PM
Man I hope that thing kicks ***. You may have just cornered the skimmer market. Maybe get it patented real quick.

calvin415
07-12-2008, 04:52 PM
Don't think I could patent it, but I do hope it's a killer skimmer. :D

Here's some pics of what I did today... I need to put the bottom on it, install the output and the input, but only once it's been tested. I need to mod the impeller still if anyone knows a quick and easy way please give me a call tonight. ;)

http://i6.photobucket.com/albums/y242/calvin415/DSCN4277.jpg

http://i6.photobucket.com/albums/y242/calvin415/DSCN4276.jpg

http://i6.photobucket.com/albums/y242/calvin415/DSCN4278.jpg

http://i6.photobucket.com/albums/y242/calvin415/DSCN4279.jpg

http://i6.photobucket.com/albums/y242/calvin415/DSCN4281.jpg

http://i6.photobucket.com/albums/y242/calvin415/DSCN4282.jpg

Not too bad IMO, from nothing to this in 7 hours minus breaks...

xsocali
07-12-2008, 05:08 PM
That was quick and looks good...cann't wait for you to hook it up and see some photos of it in action.

Huhhhhh
07-12-2008, 05:12 PM
I thought you were going to make it square? Looks good though.

calvin415
07-12-2008, 05:24 PM
This is just a nano test skimmer to see how well I could build the cone and get everything connected. :D This thing is tiny!!! It's powered with a MaxiJet 600, my skimmer will run with a Dart. 160 GPH vs 3600 GPH. :D

Huhhhhh
07-12-2008, 05:27 PM
This is just a nano test skimmer to see how well I could build the cone and get everything connected. :D This thing is tiny!!! It's powered with a MaxiJet 600, my skimmer will run with a Dart. 160 GPH vs 3600 GPH. :D


Thanks for your support bud! I'm going to do some test cones tomorrow and likely build a smaller prototype if anyone needs a nano skimmer.

Ahhhh, My retention is about zero these days, I'm trackin' now.

mountaindew
07-13-2008, 06:38 AM
looks good e!
i found from testing that screw threads swell slightly and get so tight that you have to put a lot of strain on everything to take it off and on. maybe you will have better luck!
I went to bayonet connections, but just one bayonet mount takes more time to make then your proto did!
they do look cool when done with clear plastic tho! :)

Jiggyfly
07-13-2008, 08:51 AM
that is a trick skimmer, way to go master of all things acrylic

ritmar
07-13-2008, 08:56 AM
Nice work Eric.

Murfman
07-13-2008, 10:44 AM
very sweet!!!! How did you get the neck done? Heating and pulling it?

calvin415
07-13-2008, 01:01 PM
Thanks guys, yes I heated the acrylic with my space heater and then pulled it over the two sizes of pipes. I need to finish the last bit of plumbing work (input and drain) and then put on the bottom. Once it's all together I'll need to find a tank to test it out on...

Murfman
07-13-2008, 01:34 PM
You should look at reverse engineering a Bubble King!!!!!

calvin415
07-13-2008, 04:39 PM
Piece of cake, the biggest issue is 1 the connection for a removable collection cup, the second is the price of acrylic tube that large. Hence the reason I'll be building mine square. :D

calvin415
07-15-2008, 10:17 PM
Well all I can say is DAMN YOU SCOTT!!!!! (I went to Brent's house when Scott was there and forgot my tin foil hat)... You got me looking at the beckett skimmers and now it looks like I will be building a dual injection, recirculating beckett skimmer. I can't find a recirc needle wheel that can handle 250 gph without building my own, and the beckett looks a lot easier since I just hook up a standard pressure rated pump and I'm good to go.

I ordered a pair of becketts on Monday, and I ordered the Jasper 400 & 200 circle cutting router guides 5 minutes ago (yes I'm going to use round acrylic tubes). For the size I want to build, it will be rated for 1100 gallons, so I think I'm going to end up going SPS due to the lack of nutrients. LOL! They recommend a feed pump of 750-1500 GPH, so I'll be lucky to hit the minimum on that. ;) Nothing like building a skimmer for less than 1/2 price. :D Think I should just build a smaller one?

Reefkoi
07-15-2008, 11:42 PM
Anyone that builds their own skimmer is cool...............
C

aquaman2000
07-16-2008, 05:55 AM
Well all I can say is DAMN YOU SCOTT!!!!! (I went to Brent's house when Scott was there and forgot my tin foil hat)... You got me looking at the beckett skimmers and now it looks like I will be building a dual injection, recirculating beckett skimmer. I can't find a recirc needle wheel that can handle 250 gph without building my own, and the beckett looks a lot easier since I just hook up a standard pressure rated pump and I'm good to go.

I ordered a pair of becketts on Monday, and I ordered the Jasper 400 & 200 circle cutting router guides 5 minutes ago (yes I'm going to use round acrylic tubes). For the size I want to build, it will be rated for 1100 gallons, so I think I'm going to end up going SPS due to the lack of nutrients. LOL! They recommend a feed pump of 750-1500 GPH, so I'll be lucky to hit the minimum on that. ;) Nothing like building a skimmer for less than 1/2 price. :D Think I should just build a smaller one?

:icon_biggrin:

mountaindew
07-16-2008, 07:13 AM
your going to like the circle jigs! they work great.
i have both but i only use the one.
i use it to make patterns out of masonite then stick pattern to acrylic with double stick tape and then route it. works perfect
oh and you will need a 1/4" spiral up cut bit as the jasper jigs are set up for using one!

calvin415
07-16-2008, 09:08 AM
your going to like the circle jigs! they work great.
i have both but i only use the one.
i use it to make patterns out of masonite then stick pattern to acrylic with double stick tape and then route it. works perfect
oh and you will need a 1/4" spiral up cut bit as the jasper jigs are set up for using one!

And the hits just keep on coming. ;) Also going to need a 1/8" bit for channeling a groove to accept the acrylic tube.

aquaman2000
07-16-2008, 12:15 PM
I can't wait to see this come together!!! Then build one for the green house when the time comes.

calvin415
07-16-2008, 02:21 PM
Sad to say it, but I will have more invested in plumbing than I will in acrylic. :(

calvin415
07-16-2008, 02:43 PM
Anyone have a connection on plumbing that can beat either McMasters or US Plastics?

4" Sch 80 Union is $41.20
1" Sch 80 Union is $7.03
1 1/2" Sch 80 Gate Valve is $21.00

Murfman
07-16-2008, 03:56 PM
I have a 1 1/4" gate valve if you want it.

calvin415
07-16-2008, 04:17 PM
Thanks Paul, but it might be tough to find fittings for 1 1/4... Really need 1 1/2 min.

mountaindew
07-17-2008, 07:59 AM
And the hits just keep on coming. ;) Also going to need a 1/8" bit for channeling a groove to accept the acrylic tube.

Why do you need the groove?
i looked at doing that before, but never figured it would add any strength to an acrylic glue joint.
are comercial skimmers built this way?

i do use a 1/8" half round router bit with jasper jig to groove plastic for rubber o-rings. works way better then a fly cutter "imho a dangerous tool in a drill press"

also you will need a plunge base for your router if you dont have one!
:)

as for plumbing parts i use indelco and savco but price is not what i look at, its getting the right part. indelco has large selection of fittings that can be hard to find. again my build does not have much room "500 lbs of stuff in a 5lb box" so i have to use all kinds of odd parts to save room! i am down to dosing pumps and ato are the last 2 things to put in the system. so its close but still not finished :(

calvin415
07-17-2008, 10:35 AM
From what I've read, everyone sets the tube in a groove for added strength. I could probably skim that step, but I figure it will just make welding the tube that much easier since there will be a nice channel for the solvent to sit in. Not too deep just 1/16" but enough to help hold it.

I'll have to find a 1/8" half round router bit so I can do the groove for the 0-rings, I hate my fly cutter!

Yeah, mine is not a plunge, but I figure I can just mount the jig to the table and then raise and lock the router into the acrylic (or just drop it onto the bit); then I can rotate the acrylic instead of the router.

I hear ya on the plumbing, I've check savko, and every other company and unless I order 1000 from China I don't think I'm going to get much cheaper than what I already posted. :(

calvin415
07-17-2008, 09:12 PM
Got my Becketts today!!!

http://i6.photobucket.com/albums/y242/calvin415/Ultimate%20Nano%20Projects/DSCN4306.jpg