Cheap Siphon Tube

[Ulu]

I found these U tubes made of polypropylene for under $5 each at Lowe's. I cut the long tails off and swapped them to make two siphon tubes. Unfortunately I didn't take a photo before I cut them.



I heat-welded this with a heat gun. It's the only way because you just can't glue polypropylene. It's the stuff they make glue bottles out of because glue doesn't stick to it.


Unfortunately I didn't get the second one quite hot enough and it didn't stick.


The large one was flawless though, and it is a big Improvement in performance over my previous siphon tube.


I didn't bother with the little bung on top this time and I just used a loose aquarium tube to evacuate the siphon.

 

[Ulu]

With the new high-performance siphon I am able to run this pump now at Speed 8 of 20 without flooding.

 

[Ulu]

I rebuilt the overflow assy to match the flow of the new siphon tube.

1.5"ABS & PVC replaced the 3/4" PVC & hose arrangement.

Flow is dramatically increased even with the 1" throttle valve.

 

[Ulu]

Main drain on the right is seen at full flow while the auxiliary drain at the left is starting to flow. The pump is 25% speed.

At 50% speed that fills both drains, full siphon, with the one-inch valves throttled about 50%. I haven't tried to run it with both valves wide open yet.

 

[Ulu]

I made a new siphon tube for my brackish tank today. It's from the same 1.25" u-tubes shown up above.

This one has a bung glued on with boat epoxy, as the overflow assy was too narrow to allow a loose-tube evacuation.



The previous tube was 3/4" sched 40 PVC that I had ported and relieved internally for better flow.

It started slowing down and requiring weekly cleaning because of the salt water. The new one flows 50% better

 

[Ulu]

A shot of the brackish tank.

 

[Ulu]

The slightly ragged area is a heat weld, and I simply heated the two 1.25" tubes and butt-welded them together.

 

[Ulu]

Motumbo is King of the tank, and now over 6" tall. Black mollies are little pigs and clean up the slops.