Plumbing theory...

[AndyL]

Quick plumbing theory question,

Adding an above tank fuge, feeding it from the sump by a separate pump. Ideally we'd like it to overflow into the main tank.

What would happen, if the overflow from the fuge, was tee'd into the feed to the display tank?

Something bugs me about T'ing the two water feeds together, but I can't place it... Anyone know why this wouldn't work?

TIA,

Andy

[Conano]

I think i have an idea of what your trying to say here, but could you explain better or draw up a diagram?

[AndyL]

MS paint sucks but...

http://i74.photobucket.com/albums/i277/cgyreefer/plumbing.jpg

Make sense with a picture?

For the person who PM'd about bubbles - SOS/Herbie overflow on the fuge, thus few if any bubbles will hit the drain (emergency is getting plumbed down to the sump).

[Cuervo]

It would most likely become a second feed for your fuge. My guess is the fuge drain would be the top of the tank. ;)

The reason - The pressure from your pump is going to be alot more than the pressure from the fuge.

You may be able to balance it somehow, but if any little thing ever changed you'd have troubles.

I would definitely not do that.

[clsanchez77]

You will likely take half of the water from the sump pump and return to the main tank, and the other half and overflow your fuge. Even if youy put a ckeck valve, the fuge would not be able to freely gravity drain into the tank using a pressurized line.

I would use one pump from the sump return pump, run it straight to the fuge, 'T' off it to allow some water to go directly to the tank so you can control what fraction, or all of, the water is returned to the fuge, then have a separte overflow line from the fuge to the tank. Use a gate valve, not a ball valve, to control how much water goes to the tank. You may need a second gate valve to the fuge to balance the head losses.

Chris

[lllosingit]

Why not run a small pump from the sump to the fuge and then have all of it drain back to the main tank? As long as the drain from the fuge and main tank can handle the extra water flow it would be fine.
What kind of overflow setup does the fuge have?
How much flow are you going to put thru the fuge?

The way you have it in your diagram will also work fine just as long as the main tank can handle the extra water from the fuge.

[jdieck]

What happen in that situation depends on the pressure drop on each line. Say if the pressure of the column of water from the fuge surface to the T is lower than the back pressure from the T to the aquarium outlet then the fuge will not drain and in the worst case it will be fed by the line.
What I would do is use a single return pump (a bit larger) to feed both fuge and main tank, install a valve from the T to the aquarium to regulate how much flow the fuge shall get. Then drain the fuge directly to the main via a separate pipe.

[clsanchez77]

Why not run a small pump from the sump to the fuge and then have all of it drain back to the main tank? As long as the drain from the fuge and main tank can handle the extra water flow it would be fine.
This would certainly work.

The way you have it in your diagram will also work fine just as long as the main tank can handle the extra water from the fuge.
It wont work, best case scenario is the head loss to the tank is less than to the fuge such that the water in the pipe sits stagnant and ther is not volume change in the fuge. Remeber water has to enter the fuge AND exit the fuge in order for the fuge to be benifical to the tank, and this can not happen with only one pipe. Your first idea of a separate pump, and jdiecks idea of a valve will work, jdiecks was more of what I had in mind.

What I would do is use a single return pump (a bit larger) to feed both fuge and main tank, install a valve from the T to the aquarium to regulate how much flow the fuge shall get. Then drain the fuge directly to the main via a separate pipe.
Because the fuge is above the tank and requries additional static lift than the tank, a valve between the tank and fuge will cause more water to go into the tank and less available for then fuge than if there were no valves. That is why I am recommending the valve either be on the tank output to balance the additional static head to the fuge, or have two valves, one to the tank and one to the fuge. Sepearte drain pipes is the only way this will work.

Chris

[jdieck]

<a href=showthread.php?s=&postid=8526716#post8526716 target=_blank>Originally posted</a> by clsanchez77

Because the fuge is above the tank and requries additional static lift than the tank, a valve between the tank and fuge will cause more water to go into the tank and less available for then fuge than if there were no valves. That is why I am recommending the valve either be on the tank output to balance the additional static head to the fuge, or have two valves, one to the tank and one to the fuge. Sepearte drain pipes is the only way this will work.

Chris
That is right that is why I recommended a valve from the T to the aquarium not from the T to the refugium.

[lllosingit]

Unless I misunderstood the origanal post, His diagram only shows the return line not the feed line.
If he splits the return line coming from the fuge why wouldn't it work?
If you run the line down to a T then have one pipe going to the tank and one pipe with a valve going to the sump you can divert as much water as you want to the main tank or let most go directley to the sump. He just has to be sure the overflow on the main tank can handle the extra water coming from the fuge.


The way he has his diagram will work...if that is his return line, He stated that he wants to use two pumps...one for the tank and one for the fuge...so both will have a set water supply..He was asking if he could split the returns...and he can. So again explain to me why this wouldn't work??

[jdieck]

<a href=showthread.php?s=&postid=8527790#post8527790 target=_blank>Originally posted</a> by lllosingit
Unless I misunderstood the origanal post, His diagram only shows the return line not the feed line.
If he splits the return line coming from the fuge why wouldn't it work?
If you run the line down to a T then have one pipe going to the tank and one pipe with a valve going to the sump you can divert as much water as you want to the main tank or let most go directley to the sump. He just has to be sure the overflow on the main tank can handle the extra water coming from the fuge.


The way he has his diagram will work...if that is his return line, He stated that he wants to use two pumps...one for the tank and one for the fuge...so both will have a set water supply..He was asking if he could split the returns...and he can. So again explain to me why this wouldn't work??

The way I understood the diagram is that he wants to connect the fuge drain to the auqarium return not to join both drains.

[lllosingit]

<a href=showthread.php?s=&postid=8527861#post8527861 target=_blank>Originally posted</a> by jdieck
The way I understood the diagram is that he wants to connect the fuge drain to the auqarium return not to join both drains.
I didn't say he wanted to connect them both.
hmmmm... I took it as the diagram showing just his fuge return line and nothing more, He's said he's adding the fuge to the tank, I took that as he already had the tank plumbed and it's not shown in the diagram.

[Cuervo]

I would Tee off the return line and use it to fill the tank and the fuge with a valve on the fuge section to control turnover there.

I agree with plumbing the drain from the fuge directly into the display. Find some black or grey PVC, or maybe paint it, and it will blend into the tank background.

[AndyL]

Wow some people really don't bother to read before posting do they...

Plan started... 2 pumps, one to feed each tank. But the fun was as the question stated, could the overflow from the fuge (above tank) T into the feed line for the display - water takes route of least resistance... it would end up in display, not creating a 2nd feed to the fuge (of course assuming no insane line pressure due to insufficient size etc).

Of course, everything changed after posting and starting to plumb, why I spend time planning I don't know :) It never seems to work the way intended...