Did you buy a SCWD and hate it?

[reefbound]

Well so did I, I built a closed loop and bought a SCWD and attached it to a Mag drive 950, I thought this would be great... Wrong! So I stop at the LFS and picked up a Mag 1200 and thought this HAD to be better, NOPE, What the hell is going on I thought I did everything right and NO pressure. So I went to the SCWD web site and watched the video about 3 or 4 times then it hit me in the head like a ton of bricks. When you build your closed loop you use 3/4 pvc pipe all the way back to the inlets right? Yes. If you look at the video there inlets are a 1/8 to 3/16 slit ... Same concept as putting your finger over the end of a garden hose,increase pressure.So instead of rebuilding my closed loop here is what I did.Took a propane torch on very low,Heated a 90 degree elbow and closed one end, Well let me tell you,Holy mackeral, Not only is it breaking the suface its creating small vortexes around the tank. Here are a couple of pics...plus I figured if it worked for the closed loop why not the return from the sump, That has a Mag 700. tank 1 pic, That shoots across the back of the tank.

 

[revhtree]

Thats cool did you get that idea for the closed loop from Melev?

I would like to see a pic of the whole set up if possible, thanks.

 

[reefbound]

Yes thats where I got the idea from,but his is on a 29 gal tank and mine is on a 75gal. Give me a couple of hours and I will post pics of the hole setup.
With those 90 degree elbows closed down it works like a charm and is whisper quiet. Before I did that the pipes were actually banging and no matter what I did it wouldnt stop.

 

[Gatorfreak]

So what was the problem with the SCWD? Was it just too much restriction on the flow?

 

[greenmaji]

Would diping the part of the pvc to be shaped in boiling water work as well? Thats what I would have tried first if I was just doing it on my own, with no advice.

 

[reefbound]

So what was the problem with the SCWD? Was it just too much restriction on the flow?

With having 3/4 of an inch all the way into the tank it seemed like the water had no pressure coming out of the inlet, When you restrict the flow at the opening it increases the pressure coming out and the result is outstanding flow...

Would diping the part of the pvc to be shaped in boiling water work as well? Thats what I would have tried first if I was just doing it on my own, with no advice.

I dont think it would have worked,I dont think the heat would be enough,although I could be wrong.

I would like to see a pic of the whole set up if possible, thanks.

Here ya go.

 

[reefbound]

A couple more...

 

[greenmaji]

looks pretty good..
how big is your tank? currious..
and all those 90 degree joints are scarry 8O kidding..

 

[runway1]

Not to be a downer but yes, you put your finger over the hose and that will decrease your flow rate and increase the pressure, thus the increased water movement.

Problem is, your mags aren't designed for back pressure. So i would suspect you'll greatly decrease their lifespan. If you don't mind replacing mags, you're fine. That's why some pumps (mostly external) are pressure rated and others are not. Some are designed to "push" through resistance of some sort (restricted opening) and some aren't.

 

[flanque]

what is the purpose of this project? i have 2x 1500L/hr power heads and a 1500L/hr canister filter which I would like to better use to eliminate dead spots and increase water flow.

 

[reefbound]

looks pretty good..
how big is your tank? currious..
and all those 90 degree joints are scarry 8O kidding..

My tank is 75 gal...

Not to be a downer but yes, you put your finger over the hose and that will decrease your flow rate and increase the pressure, thus the increased water movement.

Problem is, your mags aren't designed for back pressure. So i would suspect you'll greatly decrease their lifespan. If you don't mind replacing mags, you're fine. That's why some pumps (mostly external) are pressure rated and others are not. Some are designed to "push" through resistance of some sort (restricted opening) and some aren't.

Well I have already thought of that and Im going to contact Mag drive and see what they say...If these are designed to run for lets say 5years and I kill it in 4 then I wouldnt mind .

what is the purpose of this project? i have 2x 1500L/hr power heads and a 1500L/hr canister filter which I would like to better use to eliminate dead spots and increase water flow.

The purpose of this project is to get all the powerheads out of the tank and make some room,Large powerheads take up some prime property.And most of all is the amount of water flow.

 

[flanque]

Do you have a thread on this forum on what process you went through? I wouldn't mind having a read and see how you did it and what I may be able to apply to my tank.

 

[revhtree]

Here is the link:

http://www.melevsreef.com/closedloop.html

 

[pelochas]

Not to be a downer but yes, you put your finger over the hose and that will decrease your flow rate and increase the pressure, thus the increased water movement.

Problem is, your mags aren't designed for back pressure. So i would suspect you'll greatly decrease their lifespan. If you don't mind replacing mags, you're fine. That's why some pumps (mostly external) are pressure rated and others are not. Some are designed to "push" through resistance of some sort (restricted opening) and some aren't.

i learn something everyday. i have a Pentair Quite One 4000 ( 1017gph ) pump in my sump. i wanted to add a SCWD and some water deflectors and everything else to get water moving around the tank. but since this pump is not design for back pressure i am going to another plan. or can i add a SCWD and be safe. i have approx 5 feet of overhead and it will average about 700-800 gph. should i move over to an external pressure rated pump?

 

[flanque]

The powerheads I use have a flow control arm on them so that you can decrease and increase the flow. I would suspect these would be rated to take some of this 'back pressure' mentioned. Agreed?

They are Aqua One 1200L/hr powerheads.

 

[runway1]

All pumps take "some" back pressure. Just the physics of moving water causes that. But, when you take 3/4 diameter PVC hole and squish it to 10%-20% of the area, that's a different story.

Not that it won't work. Heck I've never tested this specific setup. I'm just pointing out a concern from an engineer's perspective. Again, some pumps are pressure rated for a reason. They are also engineered differently for those applications. Just something to be aware of.

I'd say go for it . If it fails prematurely, you have your answer. If it doesn't, you have a successful design.

 

[revhtree]

Hows that return working out in the corner?

 

[quarryshark]

I just used flexible hose on mine. Working great for over 2 years now.

 

[revhtree]

You have one of these set up Kurt??

 

[flanque]

Is there any reason for concern with chemicals "leaking" out of the plastic or sealent?