Tips and tricks tuning a shadow

[behold81]

i am starting this thread to give an area for anyone to help give tips how to make the shadow overflow silent or close to.

Issues I have found and need options.

1. Any flow in the second drain makes noise
2. Where should all the water levels be in the box. Seen a few pics but it’s unclear. In respect to holes of all pipes and the inlet.
3. Do the heights of both primary and secondary mater or just one.
4. Anything else!

Hopefully this can make a good product greater for all.

Thanks.

 

[CoralNerd]

My notes from a BRS video
• Regarding the overflow secondary see image the plumber needs to drill a hole at the top. This overflow needs to be about 3/4" higher than the primary overflow to prevent a full cyphon. Its important that it's low enough to get fully submerged if the primary backs up.
• Emergency overflow that's a open pipe at least 1/2" higher but still lower than the overflow box.

https://www.bulkreefsupply.com/video/view/week-5-plumbing-overflows-return-pumps/

 

[behold81]

It’s still not clear.

Mine is silent but every 20 secs I get a flurry down the secondary that’s noisy. I have tried so much with not avail.

My notes from a BRS video
• Regarding the overflow secondary see image the plumber needs to drill a hole at the top. This overflow needs to be about 3/4" higher than the primary overflow to prevent a full cyphon. Its important that it's low enough to get fully submerged if the primary backs up.
• Emergency overflow that's a open pipe at least 1/2" higher but still lower than the overflow box.

https://www.bulkreefsupply.com/video/view/week-5-plumbing-overflows-return-pumps/