How to start the overflow.

[Verbalkint]

Built it this evening, with 1/2" PVC..

Total cost, about $18.00 For all the hardware (Sched 40 Cold Water PVC)

I'll post some pics when I get some taken

 

[Kasakato]

Thats just what I wanted to hear! What size tank are you using it on? Can I get a list of what you used?
TIA

 

[Verbalkint]

Sure Thing:

Parts List:

10 90 Deg Elbows (.25 Each) $2.50
1 45 Deg Elbow (.35 Each) $0.35
13 T Joints (.35 Each) $4.55
1 Cross Joint (.45 Each) $0.45

10' Sched 40 PVC (2.75 Each) $2.75
2 Ball Valves (3.25 Each) $6.50
1 Can PVC Glue (1.75 Each)$1.75

Total Cost: $18.85

(Tax was included in all unit prices)

That, and about 3 hours for measuring, cutting, and assembly.

 

[Kasakato]

How did you cut and put them together? Cant wait for the pics

Also did you use 10'? or did you meen 1'?

 

[Verbalkint]

Nope, Used 10 feet (10') of 1/2 inch pipe.

My father and I cut it to size using a table saw. I think we have about 5" (inches) left over after it was all said and done.

Used a rotozip (dremmel like tool) to cut the slits in the 'strainer' parts.

I'll grab some digi pics this evening of it for ya.

 

[Kasakato]

Ok got it! I think I will use a miter saw to cut it. The feet and inches is messing with my mind because we dont use them in Canada :?

 

[BillyZ]

Ok got it! I think I will use a miter saw to cut it. The feet and inches is messing with my mind because we dont use them in Canada :?

Centimeters in an Inch

 

[bound_for_obx]

1/2 inch is approx 13mm
10 feet is approx 3 meters

 

[Kasakato]

I just was looking at my ruler and: 2.5cm= 1"

 

[No_Floaters]

This is another site that has pictures that may help you.


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

 

[Kasakato]

Not to push it or be mean: but do you have the pictures?

 

[jsoong]

I've finally found the article on aquarium plumbling ... It is at advancedaquarist.com. The article is a rather detailed engineering discussion, far more than my basic understanding on fluidics.

To make a long story short ... If I understand the equations correctly, the max flow rate of a 1" PVC overflow is around 400 gph. <I didn't worry about the elbows, etc. real number prob. a bit lower>. Since resistance in pipes varies with 4th power of radius, I would expect only 1/16 the flow rate in a 1/2" system (or 30-40 gph).

Also, it seems my idea of using a long in tank loop to enable a high head pressure to drive the siphon won't work. The resistance of the extra tubing is offsetting any gains in driving pressure.

I am just wondering if anyone has any real flow numbers to back up or refute my estimates. If my calculations are correct, I'll have to look at a different system (maybe one of those continous flow through box), as I am aiming for 800-1000 gph.

 

[PatM]

Lets see if this helps anybody. I built this simple overflow out of 2 lees specimen cups, two pet store bought u-tubes, and a bunch of 1" pvc fittings and pipe. The drain to the sump is 1" but I found that by lowering the height of the pvc in the outside specimen box it did increase flow. I also have found that adding 2 u-tubes did very little to increase the flow rate, but I don't exactly know why. The u-tubes are 1 1/4" and with this system I'm getting about 400 gph, though I still want more gph, my pump is rated at 800 gph, and I'm considering t'ing off back into the sump to reduce pressure on the pump.

 

[jsoong]

With 2 1-1/4" siphons & You are still at 400 gph, that doesn't bode well for the 1" PVC overflow's flow rate .... unless your bottle neck is at the skimmer box or the sump drain ....

I was hoping people will tell me my numbers are bull & they are getting great flow with this thing .... still waiting ....

 

[PatM]

Tested last night with a gallon jug and actually got almost 500 gph, close to what I wanted, but still I think the most reliable way is the continuos siphon overflow, the weir method if you will. Good luck, I just found that there were so many factors in siphoning that I wasn't understanding...or maybe still don't. Like lowering the height of the pipe in the outside overflow box only 1/4" increased my gph by about 100 gph. It just takes lots of prototypes, and sometimes it ends up costing more than just buying the best one you could find to begin with. It isn't any fun that way though.

 

[varga1]

one ugly thing to have in your tank