I screw up with overflow design. Please need help to fix

[mare021]

Hi, I'm new in reefing and build my first reef tank. It's 40 gallon tank. It has one return 25mm pvc return line powered with DC pump. Tank has external overflow box with three 40mm pvc pipe drains into sump, like bean animal style but I tee primary and secondary line in order to connect both lines on rollermat. I muffled sound from secondary drain in overflow box with maggie muffler, but water running through pipes in cabinet is still very noisy, the loudest near the tee fitting where pipes are connected. I tried to reduce outline diameter, and reduce flow with pump but, it's still noisy. I had idea to put another gate valve on secondary drain in order to reduce amount of air entering the tee, but I'm not sure if it's worth. Any idea how to fix?

Thank you

 

[KStatefan]

Separate the full siphon and the secondary.

 

[theMeat]

Separate the primary and secondary. The primary and secondary pipe should end slightly below water level in sump or you’re going to hear it. The emergency drain should end above the water level in the sump so you CAN hear it

 

[mare021]

Thank you for your answer, but that means that only primary siphon can be connected to rollermat since it has only one input. How to connect secondary drain? I want to make it go through mechanical filtration too? Is there any solution for that?

 

[KStatefan]

Thank you for you answer, but that means that only primary siphon can be connected to rollermat since it has only one input. How to connect secondary drain? I want to make it go through me hanical filtration too? Is there any solution for that?

Don't worry about the 2-5 % going thru the secondary

 

[RocketEngineer]

Like above, you don’t need to filter the secondary drain. And if tuned correctly the secondary drain should be almost no flow anyways. The siphon should handle as much flow as possible and exit just under the surface to keep noise to a minimum.

 

[theMeat]

Like above, you don’t need to filter the secondary drain. And if tuned correctly the secondary drain should be almost no flow anyways. The siphon should handle as much flow as possible and exit just under the surface to keep noise to a minimum.

This ^
fwiw, many ppl, like myself, don’t run any mechanical filters and have successful tanks. Don’t sweat it

 

[Syntax1235]

The second drain is the open channel, it should have some kind of tubing on the top of an elbow so it can become a full syphon if the main syphon becomes blocked. Here's a picture of mine:


Notice the water level. Water is trickling down the open syphon. Should the water hit the blue airline tub it will purge all air and become a main syphon. the filter sock in this picture is on the emergency channel because I have just added pods to the tank and don't want them to get caught in the sock.

The maine siphon is completely submerged. The open channel needs to be higher than the main siphon so that it does not become a siphon upon start up. Water should go into the open siphon upon startup, but it should never become a siphon because the main siphon will purge air first. There's a 5000 page thread on Reef Central created by Bean Animal, you can still find it in the archives.

Also, there should not be any horizontal runs. The gate valve on the main syphon should be as close to the outlet as possible and exit into the sump no more than an inch... if it is deeper it will be harder for the main siphon to purge the air.

 

[mare021]

Thank you all for your advices.

 

[mare021]

I did replumbing, but issue is still present

 

[mare021]

 

[mare021]

 

[mare021]

This is the sound near the gate valve. It's the loudest there. I did everything except, I can't lower the gate valve because of the rollermat.

 

[BZOFIQ]

Do you have enough water going through to create a full siphon on the primary?

 

[BZOFIQ]

I believe this is your issue with primary. It's too high to create a clean full siphon.

Does the water in your box extend well above the screen? Remove it to see how it changes things.

 

[theMeat]

That may be it ^
It takes a minute or three to purge all air from pipe to achieve full siphon

 

[mare021]

I believe this is your issue with primary. It's too high to create a clean full siphon.

Does the water in your box extend well above the screen? Remove it to see how it changes things.

Yes, I remove it for test purpose. It's displayed on newer image. It's about 6" below the water surface in overflow box. Almost all water go through siphon, although there's some air in pipe below the gate valve that I don't know how to get rid of it.

 

[mare021]

That may be it ^
It takes a minute or three to purge all air from pipe to achieve full siphon

The most of water go through primary siphon, just very small amount drop down through secondary drain, but it seems that there's always some air in pipe below the gate valve. I can see it through soft tubing. It's hard to picture it, but can be clearly seen.

 

[theMeat]

Are you blowing bubbles from the primary line into sump?

 

[mare021]

Are you blowing bubbles from the primary line into sump?

I'm not sure if I understood question correctly cause I'm not native speaker. I see and hear bubbles gurgling in primary siphon just below It's gate valve. Not on exit in sump, but higher in pipe near the gate valve.