coast to coast or Durso, Herbie???
 

Well, I'm planning oour next tank. Either way, tank will be 150+g leaning on 180-210!??! Researching other overflow designs. Present tank, is Durso style, only because I was to impatient to learn and drill more holes for a herbie style with the gate valve and Emergency drain. I'm really liking some of the Coast to coast drains I have seen limeted pics of. PVC pipe with a slot in it, and holes in back of the tank, not bottom.

Few questions on the CTC design. Do they make alot of noise? My Durso, I get noise from the air being introduced in the vent and sucked down into the sump. Not alot, but its an erratic bubbling. Some pictures of peoples different CTC designs would be cool for design ideas.

Thx in advance

PS, A wavebox is in the plans too, so does this affect the operation?

One of my favorite links on the subject, this would be a coast-to-coast (caflo) with syphon (herbie):

http://www.beananimal.com/projects/s...ow-system.aspx

There was debate one someone's build thread a couple weeks back about surface skimming on a coast-to-coast overflow versus a small overflow with teeth, to create more vacuum to pull surface slime from across the tank; or something to that effect .. spshelps will chime in, he was the poster :)

I'm running a coast to coast or "Calfo/Herbie" on my 120. It's similar to the one in the post above but I only used a single siphon (downturned elbow) and a single emergency (upturned elbow). To regulate flow I have a valve between the siphon and sump. Has worked perfectly and is silent once the level in the overflow is adjusted with the valve. The emergency drops straight down to the sump and stops about 2" above the water level so you can hear running water if it's working. I've only had to rely on the emergency once (plugged the siphon with a bag while acclimating a coral) and it handled all the flow. Here's a pic that shows the emergency side:

http://www3.telus.net/lucas-mustangs...4-08%20003.jpg

I went with this design after visiting a few LFS's and noticed a film floating on some tanks equiped with just a corner overflow. I also liked the idea of only drilling the tank at the top rear as the pressure is significantly lower than near or through the bottom. Plus it was cheap! Just the plumbing and two pieces of glass:biggrin:

If you're getting the tank custom built, I would seriously consider doing the coast to coast overflow into an external overflow box, then you have no worries about drilling the actual tank and can do a proper herbie.

I had a coast to coast internal in my last tank (5 ft) but in this one went to a smaller external overflow box. I'm much happier with the external box but am kinda wishing I had done a coast to coast overflow instead of just 12 inches. That being said, my wavebox would NOT work as well if i had done a coast to coast so I guess it's a bit of a trade-off

That is the only style Ive seen so far. The link that nazarine posted has 3 drains, with gate valves. Does your main drain have a gate valve? Is it dead silent? My 45g in the living room makes about as much noise as we can handle. My goal with the new tank, is make it 4x larger, yet more quiet.

Ohh, never thought of that. A wavebox is in the plans. How does this affect things?

Tunze recommends a center overflow with the wavebox. I have a single external corner overflow with a herbie drain and it took me a long time to figure out how to deal with the wavebox and keep stable water levels.

My system is silent (except some sound from my return pump...Quiet One?..yeah right!) but as it's an in-wall it's barely noticeable. Probably easier to show a pic to explain:

http://www3.telus.net/lucas-mustangs/AQUA/plumbing.jpg

The overflow plumbing is all 1.5" PVC. From the overflow it goes to a "T". One leg goes straight down to a ball valve, the other leg goes across to the "fuge" side of my sump where it elbows to an exit below the water line. The ball valve on the bubble trap side of the sump also exits below the water level. I think this is key in keeping it silent. I think I got lucky in that the return flow from the Quiet One 6000 seems to match up well with the overflow plumbing so not a lot of fiddling was required. By adjusting the ball valve on the overflow I control both the level in the overflow and also how much water goes to the fuge. The baffle for the fuge is sloped at about 50 degrees so that rather than tumbling over a cliff the water "slides" down to the center return section and creates no noticeable bubbles.

This was a standard tank and as Slick Fork suggested, if a custom tank I would have gone with an external overflow so it takes no in-tank real estate plus it would look a lot cleaner. I will be going all external on my planned "monster tank" that I will hopefully start this summer.:biggrin:

Anything other than a Herbie, air is drawn in and you'll get gurgling.