diy overflow

[rcarbonell]

I showed that pic in my lokal forum, and one guy buildt a similar one.
He also added a one-way valve (dont know is that the correct word for it)
so it dont lose its prime.

How does this work? where do water come from and where does it end up??

 

[aropal]

The problem is that during a power outage, the return hose will drain into the sump, and then siphon would be lost.

Back siphoning from the return hose is commonly fixed by putting a couple of small holes just below the water line on the return tube as has already been mentioned.

Also, this would not effect the siphonic overflow if it used a surface skimmer rather than open down tube anyway for the inflow.

The only problem I see with using a venturi would be the ability of the venturi to produce enough pressure to lift the water the height of the siphon U tube.

Since the siphon U tube has to go over the edge of the tank, it produces a vertical column of water this height. This weight of water produces a negative pressure on the venturi injector which it must overcome before it can inject the air.

So the question is how high a column of water could the venturi produce?

Edited to add:
It was Nolapete and Dr. Joe who mentioned the anti siphon holes on a sump return on this thread: http://www.monsterfishkeepers.com/forums/showthread.php?t=94626

 

[akr1219]

I seem to be having a problem with my setup. It has been working perfect ever since i got all the bugs worked about about 6 months ago. Well last week i did a big water change and had to suck the air out the start the siphon again, well everything is working again but it is making a really loud noise. Seems like the pipe going into the sump is creating all the noise? How do i stop this and why did it suddenly start?? Thanks

 

[crazysteve]

thx for the link and the info

Kool

 

[spoot]

has anyone used a durso on their overflow?

 

[aropal]

The part of the Durso you are talking about is I presume the down turned input pipe with the breather hole at the top?

Usually Duros are used in bottom drilled tanks in the overflow compartment. You will be using a siphonic overflow so only the down turned induction pipe will be relevant.

This will reduce noise on the intake if you are having a problem with that but it will bypass your surface skimming capabilities. When used with an overflow compartment in a drilled tank of course the overflow into the compartment will provide surface skimming.

A lot of people don’t run surface skimming as part of their filtration and seem to get by but it does help so it’s a matter of whether your induction is too noisey.

How are the Spoot tube experiments coming along?

 

[spoot]

Thanks for the explanation, it was pretty much what i though.

No experiments by me yet. Haven't had the time with midterms coming up.

 

[Derpeder]

I'm thinking about building this for my overflow. I love the way it looks and sucks from the bottom. My tank is acrylic. Will sylicone work or is there a different product that will stick better to acrylic.

 

[Danh]

That will work, but will drain your tank in the event of a power outtage.

 

[Derpeder]

That will work, but will drain your tank in the event of a power outtage.

No it wont. The design is explained on page 30. I'm just wondering if sylicone is the best to use on acrylic.