Nice Cheap DIY Overflow

[lshin037]

Originally Posted by Covey

Here it is. It was easier to build than it was to figure out. I tested it in the basement in a tub with water from the faucet. Max out of the faucet was 500gph and the overflow worked fine . I was shooting for 700gph but I don't have anyway of testing it until I get my pump. I turned it on and off to test the siphon and it worked perfect. I think the grey PVC is going to look good and it only made the budget skyrocket to like around $22 dollars. I will post a pick of it on the tank when I get my pump.

Hello.
Searching for a way to build a simple overflow, I came up on your idea. I have a few questions and would greatly appreciate it if you could help me out. The little valve that's on the top U-tube....is that for sucking out the air bubbles trapped inside? If so, how did you get it in there?

[Covey]

WELCOME TO 3REEF!
Your right that is just a check valve to draw air out of the top out the U. It isn't wholly nessary because air never seem to build up but it does make it easier to prime. You just suck air out of it until it start working. I have had thing for 9 months now and it has NEVER lost it siphon.

[lshin037]

Originally Posted by Covey

WELCOME TO 3REEF!
Your right that is just a check valve to draw air out of the top out the U. It isn't wholly nessary because air never seem to build up but it does make it easier to prime. You just suck air out of it until it start working. I have had thing for 9 months now and it has NEVER lost it siphon.

Thank you.
So is it possible to prime it simply by sucking on the vent tube?

[Covey]

Yeah you briefly start your return pump to get the water level nice and high then turn it off. You suck the air out of the U thru the check valve until you hear water running out of the overflow and then it is primed.

[lshin037]

Originally Posted by Covey

Yeah you briefly start your return pump to get the water level nice and high then turn it off. You suck the air out of the U thru the check valve until you hear water running out of the overflow and then it is primed.

What kind of valve is it? Is it readily available anywhere? And how did you get it on there? Sorry to bother you with all these questions. It's just that I've been looking for simple pipe-only designs and only found one...the one that was previously mentioned. Your design would eliminate so many hassles that I had to deal with the current one. Thanks for your help!

[Covey]

It is just a airline check valve. The kind you put on an air pump so it doesn't back siphon. I got that one at Walmart but you can get them at any fish store.

[lshin037]

Originally Posted by Covey

It is just a airline check valve. The kind you put on an air pump so it doesn't back siphon. I got that one at Walmart but you can get them at any fish store.

Thank you for your help.

[JayKaye]

Originally Posted by Covey

Before someone asks. The front U hangs in the tank. The back U hangs out of the tank. Water flow in thru the short open pipe,up and over the side, and out thru the T. The tall open pipe is a vent and you use it to prime the overflow.

Firstly, good job on the DIY overflow. I really like this design and may do it myself on my 110gal tank.
I have 2 questions though.

#1. "The tall open pipe is a vent and you use it to prime the overflow". Is that bit really needed? Cant you prime the overflow with the airline check valve, thus eliminating the need for the open pipe?

#2. How big is your sump tank for this? If power is lost how much room do you have in your sump for the extra water coming in from the syphon?


ATM I have a canister filter and I want to replace it with something similar to your DIY job. So any ideas or help would be greatly appreciated.

Thanks

[Covey]

Hello,
1. I use the check valve to prime mine normally too. Using the vent to prime is just an option. The vent(open pipe) has to be included because it keeps the a siphon from forming, post overflow in the pluming leading to the sump. It doesn't have to be as large you can use a small dia. pipe for the vent. I just had extra to use.

2. 38 gallon rubbermaid container from Wal-mart. The amount water that ends up in the sump when you lose power will depend on how your overflow is set up. Mine adds an extra 3" of water to the sump when the power is off. My overflow adds the amount of water in the width of the strainer pipe. If you build a oversized overflow and don't drive it every hard the level is actually less.

Anymore questions feel free to ask.

[JayKaye]

Thanks for the replies. I will be making this DIY overflow soon hopefully. Ill keep in touch if I need help.

I think ill make the vent smaller, much smaller. All it is used for is drawing air in to keep the syphon going, right?

Thnx again.