Is there a way to make a return act like a Vortech?

[Anonymous]

That's the sound of a return being made to act like a Vortech.

I asked for that. :lol:

Tom, what if you fed the water into a reverse overflow kind of setup? Wouldn't that diffuse the flow enough without reducing it too significantly?

To be absolutely honest, I'm not sure I understand what you mean.

 

[Anonymous]

Ok, you know how some systems have an intake box that is an overflow inside the tank with notches cut out? (Remember, I'mma old skool gal, k? there may be better technology out there that I'm not aware of.)
What if instead of using something like that as the intake only you have another one for the outlet? Let the box fill up, which should allow most of any possible microbubbles to dissipate, from the bottom, and then it flows out in a waterfall. Make it an inch or so higher than the intake's water level so that you're certain of no microbubbles, and I think that you can cut either a sufficient number of, or large enough of an opening notches so as to not reduce flow, but instead just diffuse it.

It's an intake in reverse. Just make it deep enough that the microbubbles have time to come to the surface and dissipate.

 

[Anonymous]

So if I take a pump that has 1" outlet, are you saying that it will move the same volume of water at 10' vertical height regardless if I use 1/2" pipe of 4" pipe, just at different velocity?

No, it will actually move more water (gph) in the larger pipe to a certian extent. In 10ft you probably would not notice the diference. In 1000 ft you would. Here is why in a table.

Ya, I understand friction loss. But if you have a pipe that is, say, 12" on a pump with a 1" output, it's pretty much like having no pipe at all. Sure, there's virtually no friction loss, but the water isn't going to go as high as a smaller diameter pump. It'll move the same amount of volume at the pump's output, but not at all heights. But I guess between 1" and 1 1/2", it shouldn't behave that much differently (though it did with my Iwaki 30RLXT )

It's like having no pipe until it fills with water, then it it a really big pipe. The volumetric flow of the pump will be more in the larger pipe because of less friction. The diamer of the pipe does nothing to the pressure the pump sees. Only the height matters to the pressure.

Between the 1" and 1.5" the flow in the 1" will be faster they should pump to the same height.

Height matters for pressure, but wouldn't a bigger volume pipe cause more energy dissipation? All the water that isn't moving one direction isn't causing more head pressure, but it is causing energy to be wasted. I can't imagine all water flows as uniformly in a bigger pipe as it does in a smaller pipe. But i don't know how much friction offsets this either. All I know is I could pump higher with 1" pipe then 1 1/2" pipe (over the span of about 20 minutes).

If what you are saying would be true then pump vendors would list max pipe sizes and the max pumping height would also have a pipe size listed with it.

I am guessing that in you example the 1.5" tubing being 2.25x larger in area and therefor volume just was going to take much longer to fill. As the water got higher in the tubing the pump rate (GPM) got slower. For a talking point say it took the 1" tube 10 seconds to fill the first foot, it took the 1.5" 22.5 seconds for the first foot, the 1" took 15 seconds for the next foot the 1.5" took 33.75 seconds, etc, etc, etc.....

Or the 1.5" tubing was flexable and you had a kink or pinch that was obstructing the line.

Pumps do not care about pipe size, just pressure. They are really simple machines.

 

[Anonymous]

Ok, you know how some systems have an intake box that is an overflow inside the tank with notches cut out? (Remember, I'mma old skool gal, k? there may be better technology out there that I'm not aware of.)
What if instead of using something like that as the intake only you have another one for the outlet? Let the box fill up, which should allow most of any possible microbubbles to dissipate, from the bottom, and then it flows out in a waterfall. Make it an inch or so higher than the intake's water level so that you're certain of no microbubbles, and I think that you can cut either a sufficient number of, or large enough of an opening notches so as to not reduce flow, but instead just diffuse it.

It's an intake in reverse. Just make it deep enough that the microbubbles have time to come to the surface and dissipate.

Ah, thanks, that makes sense. Not sure if my DIY/custom request in Japanese skills are up to it though.

And I want a more powerful flow than that maybe. Unless the reverse overflow was big/high enough, wouldn't it be only a trickle?

 

[Len]

I always though max head was measured by a straight vertical pipe the diameter of the pump's output. I actually have no idea.

 

[Anonymous]

I always though max head was measured by a straight vertical pipe the diameter of the pump's output. I actually have no idea.

Max head is just pressure. Ft/2.31 gives you psi for fresh water

 

[Len]

That makes sense. I'm still not getting how pipe diameter doesn't effect maximum pump height (other then frictional loss) . At 60 psi, i can shoot water farther through a 1/4" tube than a 3/4" garden hose. I realize the volume may be similar and the velocity changes proportionally. I'm a lost cause. 8)

 

[Ben1]

I dont get it either Len lol. I use the head loss calc and see that no matter the pipes size the vertical height it can pump doesnt change. I would think that a larger pipe having more water weight to move would effect the height that the pump can push water to, but I guess I am wrong. It seems the GPH actually do go up when the pipe diameter gets bigger, no matter the height its pumping to.

 

[Len]

I dont get it either Len lol. I use the head loss calc and see that no matter the pipes size the vertical height it can pump doesnt change. I would think that a larger pipe having more water weight to move would effect the height that the pump can push water to, but I guess I am wrong. It seems the GPH actually do go up when the pipe diameter gets bigger, no matter the height its pumping to.

I understand what Mark is saying, that there isn't more weight to push (only the water above the pump matters since it's singular downward gravitational pressure). But the thing that confuses me is if you have X psi of pump force, the more narrow the pipe, the faster it flows and the farther it shoots out of the nozzle. But I guess what Mark is saying that if it's in the pipe (never exits), then it doesn't matter. Still can't wrap my head around it though

 

[bfessler]

Hi Tom,

Boy there is a lot of technical talk going on over a fairly simple question. I am coming in late on this thread but I just built a frag tank and designed a return that gives a gentle flow throughout the tank. What I did is use 2 spray bars, one at the top of the tank and one mid way down. I drilled 1/4 " holes the entire length of the pipe but on the bottom spray bar I included holes that spray slightly up, straight out and slightly down. The end result has been a lot of flow in a gentle current. Here is a picture of the frag tank.

 

[Anonymous]

Thanks Burt. That's really useful. I'm thinking I might try the option I posted the pict of on page 1 - same idea (the spray bar), but only one. But I know I'll umm and aaah until the final moment, as I'm not convinced it looks that great for a display tank...

 

[bfessler]

I guess it depends on how you conceal it. I would do it differently in a display tank. Perhaps a spray bar running vertically up each corner and across the top for surface agitation leaving the center back clear of any plumbing. I liked the clear spray-bar in your picture as it's much less conspicuous than the white PVC. The spraybar across the top is nearly unseen when viewing the tank inless you are going with a rimless, hoodless design. I am very happy with the amount of flow and the gentle movement of the water which is what I was shooting for in the frag system. I can put frags anywhere in the tank without having to worry if they get blown away.

 

[Anonymous]

Hi Tom,

Boy there is a lot of technical talk going on over a fairly simple question. I am coming in late on this thread but I just built a frag tank and designed a return that gives a gentle flow throughout the tank. What I did is use 2 spray bars, one at the top of the tank and one mid way down. I drilled 1/4 " holes the entire length of the pipe but on the bottom spray bar I included holes that spray slightly up, straight out and slightly down. The end result has been a lot of flow in a gentle current. Here is a picture of the frag tank.

Like most topics there is more than one discussion going on.

 

[Anonymous]

If you do not like the spray bar you could build a diffuser box. The one I am thinking of would have two plates wth holes in them offset. Think of a wet dry drip plate with the hole of one plate in the empty space of the other plate. To feed it have a vertical spray bar with the holes sideways behing the inner plate. I would make the inner plate holes 1/4" and the outer 3/8". You need a little resistance on the inner plate to get the flow to spread. If I get time I will draw it for you.

 

[Anonymous]

What are your thoughts on the spray bar Len? My main concern is that it will lead to a very strong jet of water from the hole nearest the sump and a piddling flow from the furthest hole.

Depends mostly on how big and how many holes you make on the spraybar. If you make them too big they will do exactly what you're describing. Too small and you'll get uniform pressure but it will be a very narrow high velocity stream. You have to play around with it.

 

[Anonymous]

If you do not like the spray bar you could build a diffuser box. The one I am thinking of would have two plates wth holes in them offset. Think of a wet dry drip plate with the hole of one plate in the empty space of the other plate. To feed it have a vertical spray bar with the holes sideways behing the inner plate. I would make the inner plate holes 1/4" and the outer 3/8". You need a little resistance on the inner plate to get the flow to spread. If I get time I will draw it for you.

I am not picturing exactly what you are describing Mark, but this is essentially how you can add flow to certain jelly tanks (like for upside downs). Very low velocity by diffusing it across a plate with a large surface area.

The other option is to create something like the reverse of an overflow box. Return the water to it pointed down, and water spills out the top. High flow, very low velocity.

 

[Anonymous]

Ok, you know how some systems have an intake box that is an overflow inside the tank with notches cut out? (Remember, I'mma old skool gal, k? there may be better technology out there that I'm not aware of.)
What if instead of using something like that as the intake only you have another one for the outlet? Let the box fill up, which should allow most of any possible microbubbles to dissipate, from the bottom, and then it flows out in a waterfall. Make it an inch or so higher than the intake's water level so that you're certain of no microbubbles, and I think that you can cut either a sufficient number of, or large enough of an opening notches so as to not reduce flow, but instead just diffuse it.

It's an intake in reverse. Just make it deep enough that the microbubbles have time to come to the surface and dissipate.

The other option is to create something like the reverse of an overflow box. Return the water to it pointed down, and water spills out the top. High flow, very low velocity.

8O

Either I've been foed, or I'm living in a dream world.

 

[Anonymous]

Like most topics there is more than one discussion going on.

I think he realised that and was just being kind as I struggled to keep up!

Thanks for the suggestion about the diffuser plate! Yet again, I'm struggling to visualise it, so a drawing would be really helpful.

Burt, good points about the spray bar. I'm thinking it might work to have it lowered a touch and moved to the back (with a pipe concealed by the return column taking it there). That way you get the dispersed flow, but without the obvious pipe (some of it will be visible, but some will be concealed by rockwork).

Matt, Marina - great idea on the reverse overflow and it's not starting to get clearer in my mind how it might work! I guess the return pipe might come out of the return column and come down again behind an acrylic box?

 

[Anonymous]

Can you visualize an intake? Visualize the box (usually acrylic) that takes up a corner, side, or is even in the middle of the tank (depending on how it's plumbed). Personally I'd have the outlet coming up over the edge of the tank and down into the overflow box, to the bottom, leaving about 2".

Ha! Found a good one. Gut this internal overflow, get rid of the jets (because you don't need 'em going in this direction), and there ya go.

 

[Anonymous]

That makes sense. I'm still not getting how pipe diameter doesn't effect maximum pump height (other then frictional loss) . At 60 psi, i can shoot water farther through a 1/4" tube than a 3/4" garden hose. I realize the volume may be similar and the velocity changes proportionally. I'm a lost cause. 8)

The reason is fairly simple, and I may have danced around it a bit in the other thread. When water is in a pipe, the ONLY place for it to go is "UP" (the other direction from the pumped water), once it hits the open air all bets are off, it can go anywhere up, to the side, everywhere. Now the reason why it goes further from a 1/4" tube than a 3/4" garden hose is it will have faster velocity at the end of the 1/4" tube, but once it hits the open air it's simply a matter of faster velocity makes it go further, and all pressure arguments about head height go out the window.