Overflow box trouble

[Brand00995576]

But what about a bigger utube

 

[Jamie Allbritton]

If your over flow is 800 gph and your pump is 500 gph it will run at 500 because that's all you are pumping

 

[Brand00995576]

Its rated for 800 but it doesn't seem to be able to do even 250

 

[Jamie Allbritton]

With a bigger tube you may have problems keeping the tube primed

 

[Jamie Allbritton]

With the bubbles gone out of the tube it will run at 800.

 

[Jamie Allbritton]

Actually 500 because of pump speed

 

[Brand00995576]

Ohhhhhhh omg that is so much more helpful thank u I will try it with zero bubbles to start with

 

[Brand00995576]

Thank you i could not understand what that guy was talking about pressure and stuff

 

[Jamie Allbritton]

You're welcome.

 

[Dom]

Do u think a 1.5 inch tube would work better

I think it would be a good idea to post a video so we can see exactly what is going on and advise on how to fix it.

 

[mcarroll]

Yes, a pic early in the thread would have helped That Guy a lot.

Just to pile on: No air is supposed to be in the U Tube. (This was hinted at early on, but it wasn't clear.) Clearing the air in that tube is supposed to be the first step in starting up one of these drains. (Doesn't look like they provide any instructions, at least on the website.....something to consider concerning future purchases from them.)

Also, the flow rate you should target with one of these drains is around 50% of it's maximum rating. More than will work, but tends to cause noise and bubble issues, making the drain harder to live with.

The normal guidance for return pump selection – which recommends 2X to 4X the size of your display in GPH – should land you in about that 50% range. i.e. A 100 gallon tank needs about 200-400 GPH of return flow.

(Remember that this is not the same as your pump's or drain's "nominal GPH" rating.)

 

[Brand00995576]

I can't post a pic now but I will when I get home

 

[jd371]

I have the same overflow. There shouldn't be any bubbles in the U-tube at all. Are you using the stock drain pipe that came with it or did you swap it out for DIY stockman standpipe? The stockman cuts down on the gurgling and I can also adjust the level in the overflow by moving the air hose up and down.. I'll take a video of my overflow in action and post it when I get home.

 

[Brand00995576]

Good news it was just like Jamie said i got all the bubbles out and turned the pump up and it works great no siphon loss and it pulls 500 easy

 

[Dionysos25]

If anyone is looking at this, and having the same problem, I have this same overflow, and the overflow tube was too close to the bottom of the intake box, so it was restricting there.

 

[Dom]

If anyone is looking at this, and having the same problem, I have this same overflow, and the overflow tube was too close to the bottom of the intake box, so it was restricting there.

@Dionysos25

Thank you for taking the time to respond to such an old thread. Actually, I'd given up on this problem and was only using 1 of the 2 available tubes.

I attributed the issue to be related to the head height from the return pump. This overflow was installed on a 40 Long with a Danner 550gph pond pump. It worked perfectly.

But when I moved it to a 125 gallon setup, one tube kept losing its siphon. The head height increased by 27 inches. So I concluded that the pump couldn't provide return volume equal to drain volume.

To your point, I've dropped the overflow box deeper in the tank, increasing the space between the tube to about 1.25 inches from .5 inches.

Everything seems good, but I will monitor throughout the day as this sometimes takes several hours to work.

Thank you again!
Dom