What is a "full siphon" drain?

Rybren · 01/01/2010, 08:41 PM

When I read about drain set ups, people often talk about full siphon drains. Although I think I know what they mean, I'm not 100% sure.

Here's what I think. Please correct me if I'm wrong. The water level rises to a point above the drain opening, it then starts to flow down the drain and creates a vortex. The water level stays about 1/4" above the drain but hugs the sides of the drain as it flows down.

Am I close?

nikon187 · 01/01/2010, 10:00 PM

no a full siphon doesn't have any air involved. Usually when people utilise this setup they also have an emergency drain plumbed higher in case something blocks the primary drain. By having the drain a couple inches under water in the over flow, no air gets into the pipe so no noise or microbubbles. You are running the drain to max capicity or full siphon. Also called the herbie method or bean animal method ( his name and it incorperates 3 total drains, 1 primary and 2 back up)

Rybren · 01/01/2010, 10:08 PM

Okay,

Then in my example above, the drain is not operating at full capacity because it is sucking air in along with the water.

Thanks for the explanation.

BigMike75 · 01/01/2010, 10:31 PM

Correct, I tried a full syphon on my 90 and it sucked alot of air because my return pump was not close to what it could handle. The drain was a durso and I had one cap with a hole and one without a hole. When I found the correct size hole it was pretty quite.

01/01/2010, 08:41 PM	#1
Rybren Registered Member Join Date: Apr 2009 Location: Ottawa, Canada Posts: 1,642	What is a "full siphon" drain? When I read about drain set ups, people often talk about full siphon drains. Although I think I know what they mean, I'm not 100% sure. Here's what I think. Please correct me if I'm wrong. The water level rises to a point above the drain opening, it then starts to flow down the drain and creates a vortex. The water level stays about 1/4" above the drain but hugs the sides of the drain as it flows down. Am I close? __________________ 120G Mixed Reef, 28G AIO zoa/pipefish tank

01/01/2010, 10:00 PM	#2
nikon187 Registered Member Join Date: Jul 2008 Location: Edmonton Alberta Posts: 4,717	no a full siphon doesn't have any air involved. Usually when people utilise this setup they also have an emergency drain plumbed higher in case something blocks the primary drain. By having the drain a couple inches under water in the over flow, no air gets into the pipe so no noise or microbubbles. You are running the drain to max capicity or full siphon. Also called the herbie method or bean animal method ( his name and it incorperates 3 total drains, 1 primary and 2 back up) __________________ ----------------- Current Tanks: New 210 custom 84 x 24 x 24, 60g sump, SWC 250 extreme with bubble blaster 5000, 2 vortech mp40, 2 vortech mp10, 12 T5, Water blaster 5000, warner marine bio pellets, 60g clownfish cube, red carpet anemone with a 25g sump,SRO octopus 1000sss, 250w radium, lumenarc large.

01/01/2010, 10:08 PM	#3
Rybren Registered Member Join Date: Apr 2009 Location: Ottawa, Canada Posts: 1,642	Okay, Then in my example above, the drain is not operating at full capacity because it is sucking air in along with the water. Thanks for the explanation.

01/01/2010, 10:31 PM	#4
BigMike75 Registered Member Join Date: Jun 2009 Location: Mount Washington, KY Posts: 360	Correct, I tried a full syphon on my 90 and it sucked alot of air because my return pump was not close to what it could handle. The drain was a durso and I had one cap with a hole and one without a hole. When I found the correct size hole it was pretty quite.