Overflow Problems?

[jeffs86GT]

Ok. Here are some pictures.

This first picture is of the overflow pipe side.

This second shot is of the prefilter side. You can see the water is already creeping up way to high. Ignore the "sponge" thing holding up the U-tube. I took off the cover on the overflow side and it lets the U-tube fall to far into the pre-filter.

And finally is my sump. As you can see after it goes through the wall it really has no restrictions. The gate valve is there so I can divert flow towards the refuge on the left.

Hopefully all those pictures work.

Jeff

 

[sjm817]

Why the tall standpipe? The water level in the drain side has to be lower than the skimmer side.

 

[ek9vboi]

That standpipe is too long! Take it out and cut it down about half way, then take the form filter out from under the U-tube and let it just sit there. From there if it doesn't siphon quick enough then we have a new problem.

I'll post some pictures of what mine looks like when I got it.

 

[jeffs86GT]

Now that makes sense. Thats why I asked some odd posts back about lowering that. It came that way. I knew you guys would notice something right away. Now how am I going to lower it? Will loosening the bulkhead allow me to lower it?

Jeff

 

[sjm817]

Just pull it out and cut it. It shouldn't be glued in. Make it so that it is about 1/2" higher than the bottom of the U Tube. If its not higher, the U Tube wont keep a siphon.

 

[ek9vboi]

Here is a bad picture of the inside of the outter box for the HOB overflow.

Notice the pipe isnt that high, its about half the size of the outter box itself. Also, notice the U-tube it isnt sitting on anything, just the HOB overflow itself.

Notice in this picture the u-tube I was talking about cutting down. I had to cut one side of the u-tube shorter to get it to siphon quicker because I set my prefilter high.

Whatever you have in on the drainpipe remove it, looks like it is obstructing flow down the overflow into the sump. In fact, after looking at it... seems like that is restricting the drain very much so. It looks like a plug with a slit cut into it which cuts the drain down. Its hard to explain I guess if you dont understand it.

 

[ek9vboi]

Some more recent (earlier today) pictures. They are crappy as well, I was not prepared.

This is a picture of the outter HOB overflow I took. It has a Stockman/Aqua Silencer that I made that made my overflow 110% quiet... very happy and it does not restrict flow at all.

In both pictures, notice the water level. I am pretty sure it is the pipe on top of the bulkhead inside the outter box of the HOB overflow that is causing your tank to overflow.

Here is what the silencer looks like before I put it on:

The two slots I opted out and drilled holes on top and added flexable aitline tubing which made it silent. The slots sucked.

 

[jeffs86GT]

There is nothing on top of the standpipe. What you are seeing is just a piece of "flexible" airline that the Quiteflow uses to make it quiet. The height of the standpipe is definately the problem because last night I realized that the tank was not overflowing it was really trying to equalize the water levels. Now I just have to lower the standpipe. I just need to figure out if the standpipe can be removed on its own or is it connected all the way throught the bulkhead. I"m hoping that is not the case.

Jeff

 

[jeffs86GT]

Mayoboy - Since you also have this overflow, do you know if the standpipe can be removed or is it a solid piece of PVC all the way through the bulkhead down to where I have it connected to the spaflex?

Thanks again all that have replied. All those physics classes in college you would have thought I would have noticed the water levels trying to equalize.

Jeff

 

[MayoBoy]

I've never had to look as it works perfectly right out of the box. If that's the problem, why does every other Quietflo work as designed?

You have a 1" line which is restricting the flow from the 1-1/8" acrylic U-Tube and you have a tee which is causing a huge amount of turbulence and friction which is limiting the flow even more.

Before you go cutting up the standpipe, put the black pipe that came with the overflow on and see if that makes a difference.

I have to get to work now but explain to me why cutting the standpipe down will make a difference. The water isn't overflowing the outside box is it? I'll check back in an hour or so.

p.s. I just checked the black drain pipe that comes with the box. It's corrugated and 1-1/4" ID at the thinnest part of the corrugations.

 

[jeffs86GT]

Putting on the black pipe is not an option at the moment because I pvc glued on the spaflex and fittings. Sure I could cut them but I don't want to do that yet.

It turns out that I'm not really overflowing I'm just really close. If I cut down the height of the standpipe then the water level at which the water overflows into the standpipe will be less. Thus allowing the water level in the tank to be at less of a height. Those two water levels now want to be equal. Technically I really don't have to do it but I'm not a huge fan of having the water level inside the main tank be at less then half an inch from "overflowing" the display. I'd rather be able to adjust the prefilter to set the height of the water to a lower setting. Basically If I take about an inch off the standpipe I believe I'll be able to adjust the height as I want. Right now it keeps "equaling" out to the same height everytime.

Hope that makes a little sense.

Jeff

 

[sjm817]

Is the standpipe that tall stock? Not a good design. It only needs to be tall enough to keep the end of the U Tube submerged 1/2" or so. For an overflow to work well, the drain has to be lower than the skimmer level. Reach in there and give it a tug. It should come out. Its just a piece of 1" PVC.

 

[MayoBoy]

If the tank water level is up that high, it will eventually overflow. The water in the inside box should be 1/4" or so below the tank operating level. (that's how I gauge my flow rate)

Turn off the power and look at the side of the tank with the overflow. The top of the standpipe should already be lower than the normal operating level of the tank. Look at this picture http://us.st11.yimg.com/us.st.yimg.com/I/yhst-66907246933688_1905_5432973 and you'll see what I'm talking about. Run an imaginary line across from the top of the stand pipe and you should be hitting the inside box at around mid level.

Does that make sense? Since it's already lower, cutting it down isn't going to do anything.

 

[jeffs86GT]

Your right the top of the standpipe is lower then the operating level of the tank but the water in the standpipe side then rises to about an inch above the standpipe when in operation but the level in the tank is now almost equal to that height. The water keeps rising because of how a siphon works where its moving water from a higher postion (tank) to lower position overflow side. The greater the difference between the two the faster the flow. If they are equal there is no siphon and since they are so close in relative height to each other I believe its reducing the flow and causing my problems. I'm fairly certain that if I just reduce the standpipe height by just an inch maybe 2 I'll eleviate my problems.

Jeff

 

[MayoBoy]

Then ask yourself: why does MayoBoy's water only rise about 1/4" above his standpipe when he's flowing more water than I am?


p.s. I'm not just amazingly good looking and multi-talented. I've been an aquatics designer for the last 21 years or so and deal with friction, turbulence and flow rates Monday thru Friday. (Saturday and Sunday I just deal with friction and turbulence but only from my wife)

 

[jeffs86GT]

I do see your point and your definately more qualified then I am but the amount of water that should be able to pass through a 1 inch pipe even with a T in the path should be greater then whats being pumped back into the tank.

I can't currently test the black hose that was supplied because its not long enough but I might have to try something else.

Jeff

 

[MayoBoy]

Just get yourself X feet of 2" spa flex, unscrew from the bulkhead, put a foot of the black hose on the bulkhead and shove it into the end of th spa flex.

It looks like your existing lines are going into the water in your sump/fuge? That's also restricting the flow somewhat as the water has "push" its way into the reservoir which would also contribute to the back up. The friction, the tee and the submerged outlet probably all are contributing to the problem. You'll end up trading noise for flow but pulling the hoses up out of the water *might* be enough to make things work for you. Give that a try first and see if it makes a difference.

 

[jeffs86GT]

Yeah I saw that as well and was "experimenting" with lifting the end of the return out of the water. The return was working and not overflowing but my water level was still way to high. I'll experiment some more this afternoon. Thanks for the help.

Jeff

 

[ek9vboi]

Notice:

MayoBoy, can you tell me the difference please. You might have been a designer for 21 years... I am 21. But it seems like you don't understand physics at all or never took the class.

Lets say there was no standpipe on Jeff's HOB overflow, that means a lot of water would be siphon from the prefilter box in order to "equalize" it with the outter box. Correct? Yes.

Now with the Standpipe in it and with that said the height being so high, it would siphon less in order to equalize it considering that the pipe is so high.

As for the 2" flex hose, that is overduing it. You are simply underestimating the 1" hose itself. I could understand if it was the 1" hose because the outter HOB overflow box was overflowing due to the drain on it restricting it.... BUT this is the tank that is overflowing. 95% of the time, it is user error as to why a HOB overflow isn't working unless it is a CPR and be glad u don't have one of those.

 

[ek9vboi]

Normal operating:

The prefilter is taking in water at about a little under 1/2 of the box. This means that the outter box is around the same level, which it is.

That is when the pump is off. Notice the water level inside the prefilter is about 1/4 of it now. Same goes for the outter box.

Operating...

Not...

it is equalized throughout, on or off. cut that pipe down and you will see. 300gph going down a 1" drain nothing. I also noticed that the U-tube for your overflow, 1 side is shorter then the other correct? If so make sure the shorter of the two is on the prefilter side.