Unusual Myreef skimmer installation

[gregt]

I told Andy I'd take some pictures of my installation and I thought maybe someone else could benefit from the solution I came up with to make it work well.....

Basically, until I added the vent (see the link for specifics) the water level in the skimmer would not stay stable and was driving me nuts. I finally realized thanks to a discussion with spanky that it was vapor lock. The vent resolved my problem completely.

This installation is using an external pump with no holes drilled in the sump, so it's rather unusual, as is most of my plumbing.

http://www.saltyzoo.com/PhotoAlbum/p...0/setup/030110

[JDVC]

Greg,

I've been experiencing similar symptoms as well. I don't understand the problem though. How does the vent solve it? What is it venting?

Thanks!
John

[MyReef]

Thanks Greg...nice pictures!

The problem that happens is when the return or exit valve is placed under water. Even though the skimmer is elevated, it creates back pressure and makes for a quasi dump bucket.

I first discovered this right before Christmas when Eric Borneman showed me his post on RC about the skimmer doing the same. We quickly diagnosed the problem and rectified it. Greg decided to add the vent. In Eric's case we just raised the pipe from being too deep in the sump and it solved the problem also. The higher the pipe, the less back pressure.

This would only occur if you have a deep water level in your sump or you have it elevated, but a pipe draining into the sump well under water to create the presssure....it builds up..the water rises...the FLUSH.....it drains....and starts the process over again.

[tdwyatt]

Originally posted by MyReef
The problem that happens is when the return or exit valve is placed under water...

Geeze, I thought it was just my setup. I had to do pretty much the same thing, , but I resolved mine by inserting a tube from the room air up into the drain line. It now works flawlessly.

Thanks Andy! Great skimmer btw...,

Thanks for the heads up Greg, I may go back and replumb my skimmer drain with the t-fitting. I use a muffler on the exhaust on the Red sea skimmer (it did have the same problem, I now have it set up the same way for both drain lines) by taking a coke bottle and cutting the neck of of it. I stuffed it with polyester batting and placed it over the top of the drain vent. Absolutely quiet.

[MyReef]

Let me rephrase....the skimmer drain can be placed under water. I recommend that the water line in your sump be at or below the water line in the skimmer. For example, if you have a water line 2" above the skimmer box, that means you have a 10" water line in the skimmer itself. Therefore, you can have a 10" or below water line in your sump without problem.

What is happening, is that people with large sumps or people that have fish rooms want to put an extension pipe then an elbow or two down way below the water surface of the sump to help dissipate noise of water rushing out of the skimmer. With all the elbows, pipe length, and way below water surface, it creates a lot of back pressure....

FWIW, I run both of my MR-2 in sump under water levels of about 8 and 10" inches without fail or this problem. HTH and clarifies.