Durso Question
 

Is it important for a durso standpipe to have a cap on the top of it to prime it at all? I see that in this person's tank and wasnt sure if it was necessary? Or is it just there so you can shove a pipe cleaner down it to clean it?

http://www.notlehs.com/reef/salt2/durso.JPG
http://www.notlehs.com/reef/salt2/dursotop.JPG

Not to prime it no, it should have a small hole to ajust the air it will need to breath.
If you want to have it easy to clean, put a small joiner pvc near the bottom and put your durso standpipe on top of it and not glue it onto your bulkhead.

Then you can just pull out the full stem and clean it as needed.

You need the cap on top with just a small hole to adjust where your water level will be in the overflow box and to dampen the noise.

+1

How does that adjust the water level? And the hole is right in the cap?

The water level will be at whatever level the T-fitting is at.

A Durso works by allowing a controlled amount of air into the draining process. The right amount will depend on a number of factors, but having the hole on top is what allows the air to enter. Ideally, you would have some way of controlling the air that gets into the hole with a small ball valve, for instance.

The bigger the hole the lower the water level will be in your overflow (we are only talking with in 1/2" or so). And yes where you put the "T" will be where your water lever will be depending on the hole size.

Have you thought about going with a Herbie system instead?

two bulkheads in the same overflow, definitely consider a Herbie. Personally been in front of 2 high flow (1900 and 2000ggph) systems and have to say truly silent. Here's a drawing from rban on RC that shows the idea. About the only changes to it would be suggest a gate valve (easier to adjust) and just leave the secondary dry.

http://i67.photobucket.com/albums/h3...arn_herbie.jpg

That picture isnt in my tank but I do have two drains. I have 2" drains. Not sure if Im going to cut them down to 1.5 with limiting plumbing but that is the size of my bulkheads, so if I do ever want 30x turnover I can do it.

Does anyone have an article describing the build of each? Im only partially educated on the two designs but it sounds like a Herbie is better and I'd like to just do it right the first time if I can. Is a Herbie simple to install?