$15 PVC Overflow

[Gordonious]

I really have to see if I have pics of mine in my tank. Like I said that plan was much less intrusive in the tank. BTW nice tank. I love the black clown I have always wanted one.

[evilpsych]

hey.. mine's been working great in my cichlid tank.. i'm still kinda lurking around before I make the jump to SW as cheaply as possible... collecting all the info, plus acquiring free tanks is not an easy job (just got a 50gal the other day free.. and have a line on a 140gal for free too)

I think that the guy in here with a 'surface skimming' issue has some misconceptions of what he should be expecting from his acrylic overflow.. I thought that was the purpose of a skimmer down in your sump, to add bubbles to the water to grab the suspended proteins and remove them..

in order to 'surface skim', wouldn't you need bubbles? I thought the purpose of having a sump was to have a skimmer, to avoid those bubbles in your main tank? Also, it's not that much of an issue if your overflow and pump find a balance where the overflow either has a direct fall or a little whirlpool sucking said 'skimmate' off the surface.. also, break your surface tension with the return line.. it's not hard.

Once I get the size tank I want to use for a starter.. I plan on two overflows, one in each corner, setup to hug the corner with significant siphon power, and a central return.

anyway.. here's my siphon.. it's 1" PVC and it cant keep up with my return pump (a fountain pump from lowes) i wish i had made the legs longer for more flow.

[Gordonious]

I have two tanks connected currently that do not have a sump, they sit at the same level. LOTS of movement in the tanks and an HOB right on one of the tanks. Still get film, crap stuff on top of my water.

evilpsych you will see that the chemistry of the water and the way it acts is completely different with marine tanks of any sort. My hometown is also completely filled with marshes and inlets connected to the Delaware bay and the ocean and anywhere water moves slow you can see build up of "stuff". I have had between 7-3 fresh water tanks set up in the last couple of years and seen surface scum one time when I let a tank with only plants in it sit still with out a filter for at least a month. My salt tanks it's a different story. The only time I did not have surface scum to some extent is when my sump and PVC overflow were running.

My PVC overflow had three inputs which all faced up and pulled the surface down into the sump. Exchange at the surface was great.

[Casperson]

That wins the prize dude! LOL

[toastman]

I love that Gourami, I think its a new strain of REef safe fish...lol nice work

[evilpsych]

Originally posted by toastman
I love that Gourami, I think its a new strain of REef safe fish...lol nice work

geee.. all I said was I have the PVC overflow in question on my cichlid tank. 3/4 of the residents are cichlids (however small)....

way to be a jerk to those of us aquarists that *still* enjoy FW.

[jcjstl]

evilpsych i could be crazy .. i dont think he was trying to be a jerk ... i tink he was trying tobe funny yes but a jerk no ... just mho ...

[debdellac]

Can anyone help me please...I built the overflow using the original directions. Work great! except that im getting air build up in the pvc...which in turn i cant use the automatic fill up because the sump stays low and over fills the fish tank

[evilpsych]

the key to this is to have the last horizontal piece before it dumps into the sump as close to the top as possible. if it isn't, the added drop causes a siphon rather than an overflow situation. That's 99% of the problems people have with this concept, is that they think if they build it the way they want it to be, it will work the same.

Another way to explain it is this. If there is no return pump keeping the water flowing into the tank, and the pvc return has equalized the water level in the main tank, the waterlevel inside the initial portion of the overflow should be little more than the diameter of the overflow itself. It took me about 3 times building my "pretzel" to realize this. My latest design can handle about 3x the amount of water running through it, however because it is designed in this way, I no longer have issues with air bubbles accumulating in the top of the U.

The waterflow is the same, you just lose that excessive 'flush' of power when the water has to fall a greater distance to reach the equalization point. When setup as I have suggested, the overflow acts more like a hole drilled in the back of your tank than a series of PVC. Prime it once, and you end up with a rather stable system. of course, having a backup plan (aqualifter and checkvalve) are just plain smart investments.

[debdellac]

Thanks!...ill try this as soon as i can

[agreeive?fish]

I think i would just spend the money and buy me a REEF READY tank ..i think these over flows pictured inthis thread make the tank look UGLY

[Gordonious]

Why buy a 20 gallon sump when you could, "just spend the money" and buy a 1000 gallon sump? I think next time I go to pick up a bulb for my fish only tank I'll "just spend the money" and pick up 10 MH bulbs and an extra battery back up and throw away my old lighting fixture. (sense the sarcasm?)

Not all of us can just spend the money. Also how many of us do you think spend 6 months reading and planning on RC before we bought a tank and filled it with water and animals? Most people probably already have spend there money, bought and filled a tank, and have that tank just about flush up against a wall and have hardly any space for an overflow.

This thing works, is cheap, easy to make(once you understand it), and fits in a small space.

[Gordonious]

All that being said once I learned my lesson with my first salt system I saved up the money and bought a megaflow(reef ready) tank the next time I set something up. So I agree reef ready is a great idea, but it is good to have the plan around for those people trying to improve the tanks they already have inexpensively.

Jon

[pvtschultz]

Originally posted by Gordonious
All that being said once I learned my lesson with my first salt system I saved up the money and bought a megaflow(reef ready) tank the next time I set something up. So I agree reef ready is a great idea, but it is good to have the plan around for those people trying to improve the tanks they already have inexpensively.

Jon

+1 here!

[dendro982]

Sorry, missed the part about CPVC vs. PVC. Did anyone had problems with using CPVC (off-white water piping from hardware store)?
In theory, it may contain antifungal additives, may not. First-hand experience, please?

[Gordonious]

dendro982 I would post in the reef chemistry forum with that question.

[dendro982]

Sorry, direct relation to this thread - I made one for Nano-Cube, using CPVC. Was everyone used PVC only for this, or CPVC too?
Thanks.

[crazy loaches]

Okay question about optimizing this design.

I hope this wasnt already asked, I read over this whole thing a few months ago and do not believe I remember it being asked.

Referring back to the original design:

For the ease of understanbing i will refer only to the left hand side, and just realize this will also be mirrored on the right.

Would not the maximum flow be available when the bottom U-bend [part F] be as far down from the upper U-bend [part D] as possible? And to make this happen without having siphon issues then F would be the same horizontal level as B and as low as the tank allows (part B inside tank resting on bottom).

Also for maximum flow, the overflow part, the cross, should also be as low as possible so that no extra head loss is introduced, so basically part G is the minimum length just to connect the two 90's together with no space between them. In fact, downstream after part E no PVC pipe should be visible, the three 90's and one cross could all be made to connect butting together (this wouldnt make the big of difference, but just minimizing space and reduces any unnecessary length of pipe even if its horizontal.

Just wondering if I have some of the theory wrong or if there is any other reason my optimizations would work?

[tikireefer]

Bump.....good question crazy loaches........I am building one right now and I would love to hear some feed back on your questions.

[Drag Racer]

only one guy mentions the noise level. Is this set up noisy? Is there alot of bubbles that make it to the sump because it uses a durso style before going to the sump?

[tikireefer]

I thought that I would give you guys an update on this PVC overflow that I built for my 10 gallon nano tank with a 10 gallon sump. I painted the PVC black with Krylon Fusion spray paint so that it was not such an eye sore in the tank.

It is basically the same design as the original one posted here at the beginning of this thread but I made mine a smaller version to fit on a smaller tank.

Instead of using 1 1/4" PVC I used 1� and instead of 1" I used 3/4".

I had very limited space to work with since I was installing this on a 10 gallon tank, so I tried to customize the shape on the PVC so that things fit together like a puzzle and saved space. I also wanted it to be very stable while hanging on the back of the tank, so that I never had to be concerned with it moving around on me.

This is what I came up with:

Top down shot

This is a close up shot of the overflow filter I installed so that snails or fish would not end up going down the pipe.

This is the return line that I designed to fit snuggly into the plumbing of the overflow.

Top down shot

This shot shows in all put together and hanging on the back of a 10 gallon tank. Not to confuse anyone, I used my sump in these photos.

Top down Shot

This is a shot of the back side of the tank with the overflow and the return line installed.

I have had it up and running for a few weeks now and am pretty happy with it. I would suggest that an Aqua lifter be used as this really adds to the level of reliability with this kind of overflow. It would also make it much easier to get the siphon started the first time.
It is pretty quiet once it gets broken in. I am working on reducing the amount of bubbles that I get in the sump on my setup. I have the overflow dumping into the sump below the water line and I seem to be getting a lot of bubbles and salt creep. Any suggestions on that would be helpful.
I will update with pictures of it setup and running if anyone is interested.
Let me know what you think.

[Gordonious]

Have you tried opening the top cap in the middle once it is up and running? If you opened that or opened it somewhere else before it dumps into the sump most of the bubbles should escape. I'll see if I can draw another way for bubbles to get out and get back to you.

I don't think you need as much tubing in the display tank. When mine was up and running none of the tubing was in deeper then 1.5" of water so if you were standing in front of the tank you didn't even see it.

I like that you plumbed the return line in with it, that was slick. Nice paint job as well.

[Jen D]

What sort of flow are people getting through the siphon? I've read that the flow through a siphon is different than the flow through a gravity fed drain.

[dreday]

cant say for sure, but at 3/4" with 2 pipes i would say 400. if you do separate drains to the sump you should get a little more. i am looking at building one this week at 1.5" or 2" pvc. i need it for 2 75g tanks to run of one sump. with a large pump so i need around 800gph per tank.

if i ever get batteries for my camera i will post some pics of my horrible construction skillz. i am one of those guys who will plumb himself into a corner withhis arm between 4 pipes....

[Wilku]

this thing is great!