Water Flow....

[YippeeKiYea]

On a return line...
If you go from 1" pipe to 1/2" pipe, does your flow increase?, but not volume?...
Are 2 - 45 elbows better than 1 - 90 elbow?...
Any input anyone? ???

 

[katspaw]

2 45 degree would be the same as one 90 degree I would think although I havebeen told to use flex pipe to make my bends. I know that a 90 degree elbow takes away 1 foot of head. I believe the decrease in size increases the presure, as we had to decrease the water pipes in our body sprays in our shower when we installed it. HTH

Tracey

 

[YippeeKiYea]

I have used "SpaFlex" in the past, with success, but hard rigid PVC would be more appealing in my application.
Also, what about overflow line, can it run horizontally at times?...or does that decrease your gph back to sump.

...oh the addiction.....

 

[katspaw]

Now in no way am I 100% sure if this is true. But logic tells yes it will cut the gph back to the sump. Just as a 90 degree angle can cut 1 foot of head, I would think that running a gravity fed line will decrease the flow rate. It may only be a small about though. Best way to do plumbing is to put ball valves on all lines. This is a nice feature that helps when changing out pumps and other things. They can also be used to adjust flow raate.

Tracey

 

[jpelzer]

I believe that two 45's would decrease your flow less than a single 90 degree bend, although not by much. Not by enough to warrant using 45's instead of 90's if it is simpler to plumb that way.

For an overflow line, I would recommend using 45's if it allows you to keep the water flowing down at a steeper angle. Gravity is your friend in that case. You definately want to stay away from horizontal runs at all costs, always run downhill no matter what. This allows gravity to help the movement continously, plus it avoids possible bubble buildup which can cause Bad Things to happen on return lines.

And if you go down to 1/2" pipe, you'll increase the velocity of the water exiting the return, but decrease the flow rate (gallons per minute). The pressure loss due to friction for a 1/2" pipe is much higher than a 1" pipe, so you definately want to plumb as far as possible using 1". If you immediately reduced to 1/2" and ran up to the tank using that, you'd have much lower flow than if you went up using 1" and then had only a 1/2" outlet.

In reality, this higher velocity return is a false increase... Generally it would be better to return to the tank using 1" all the way. In a shower, where the fast-moving water encounters nothing but air, and is actually accelerated by gravity as it comes down, it is perceived as higher pressure.

But in an aquarium, where the moving water immediately encounters... More water... It is more useful to have more water moving slightly slower than to have a little water moving fast. The fast moving water stream will quickly lose its cohesion in the tank, and then you'll basically be losing any advantage you had, unless your outlet is DIRECTLY next to whatever item you wanted fast-moving current for.

 

[YippeeKiYea]

Thanks! Great info...

Basically I run: 1" return from pump, through 1" check valve, through 1" gate valve, then reduce to 3/4" flex tubing so I may use a SQWD and my tank has 3/4" return pipe through overflow (AGA tank). Once 3/4" pipe hits water, it goes to 1/2 flexline (which Im probably gonna change to 3/4 after this brain storm)

 

[Jcurry@wesketch]

Yippi,

I run my return line to my sump horizontally (actually 1/2" drop over 4 feet) with no problems. I have 3- 1 1/2" Durso pipes in my overflow, each one reduces to 1" flex from the overflow into an 1 1/2" pipe that runs horizontally the length of my sump and dumps the water in the sump at the far end from the pumps. I have found that running the 1 1/2" pipe horizontally slows the speed of the water and allows any air bubbles to disperse inside the pipe. It also quiets the sound of the water flowing into the sump as well as reduce the amount of micro bubbles in the sump.

I would skip the check valves in the supply lines, their a PIA and will reduce your flow. Definetley use as much flexible tubing as possible it will reduce head loss and increase flow. But it is more expensive, so use vinyl tubing approved for food & beverage contact. Don't bother with the Anderson Barrows reinforced tubing it's very expensive and IMO overkill. (by the way all the tubing on my tank is A & B reinforced tubing, I still kick myself for wasting so much money on that stuff)

I also wouldn't bother reducing to 3/4" or 1/2" pipe, just run 1" all the way.

P.S. SQWD uses 1/2" I.D. tubing to slip over it's ports. The ports are actually 3/8" I.D., which accounts for way there is such a dramatic loss in flow when using them.