Back siphon problem

boobookitty · 11/21/2017, 01:38 PM

So I've set up a reactor through which I run water from the sump. I have a pump in the sump that I have plumbed through the wall of the sump using a bulkhead to the reactor. The problem is that I need the pump to be off half the time, and when it's off I don't want the reactor water draining or siphoning back into the tank.

I've tried flapper check valves, but they inevitably fail within a few days or a week and I come back to find the reactor empty. Same thing with the push check valves, although it takes longer. I've tried a solenoid that turns off when the pump turns off, but they don't work that well: they get very hot, and fail sooner or later.

How do I plumb this so that I don't have the reactor emptying out when the pump is off?

billdogg · 11/21/2017, 02:13 PM

inline ball or gate valves would be the easiest choice.

boobookitty · 11/21/2017, 03:00 PM

Sorry, should have mentioned, the reactor pump goes on and off every 3 hours, so it’s not something I can do manually.

billdogg · 11/21/2017, 03:20 PM

Quote:

Originally Posted by boobookitty

Sorry, should have mentioned, the reactor pump goes on and off every 3 hours, so it’s not something I can do manually.

Why? Any reactor I've ever used has been on 24/7 when needed, or off, cleaned out and ready for next time.

boobookitty · 11/21/2017, 04:11 PM

Zeovit. On 3 hours, off 3hours.

mcgyvr · 11/21/2017, 04:41 PM

Quote:

Originally Posted by boobookitty

Zeovit. On 3 hours, off 3hours.

Put the top of the reactor at or below the water level in the sump..

or
Just leave it on all the time..
You likely won't see much of a difference and thats only a suggestion for when you first start using it to "kickstart" the process..

boobookitty · 11/21/2017, 06:16 PM

The reactor drains into the sump, so placing it below isn’t an option.

3 on/3 off is the standard for a nutrient-high tank, so yeah, I’m looking for plumbing options that will allow the pump to be off for 3 hours at a time without emptying the reactor.

Daddi0 · 11/21/2017, 07:10 PM

Peristaltic pump?

DreadCapn · 11/22/2017, 01:21 PM

Solution in the sister thread, here: http://www.reefcentral.com/forums/sh...98&postcount=7

ca1ore · 11/22/2017, 01:43 PM

Extend the output hose (?) of the reactor to be under the waterline in the sump - then no way for it to drain down. Otherwise a picture would help.

mcgyvr · 11/22/2017, 01:52 PM

Quote:

Originally Posted by boobookitty

The reactor drains into the sump, so placing it below isn’t an option.

It could be if you wanted it to..
You are pumping water into it.. That pressure can certainly be used to pump water up and over into the sump..

But I don't have much detail on your setup.. Pictures or a diagram of your current setup may help others provide a better solution..

A siphon break as shown by Dread above can work just fine too..

boobookitty · 11/26/2017, 08:10 PM

Update: I used the plumbing arrangement that DreadCapn suggested, and it works great: I basically built a piece that sits in the sump and replaces the internal check valve that has a pipe going up to an elbow, then a tee with an mpt-to-John Guest 1/4” adapter in the middle, then another elbow and a down pipe. The key is to make the end of the 1/4” tube above the water level in the reactor. Allowed me to remove the check valve and the solenoid valve.

Only downside is that the water shooting down into the sump is a bit noisy. I have an in-line 1/4” JG Check valve coming Tuesday (same kind used in RODI auto shut offs), and I’ll try that on the end of the 1/4” tube: should block outflowing water but allow incoming air to break the siphon. I’ll update after that.

Tripod1404 · 11/26/2017, 09:05 PM

How can the reactor drain? What part of it is in contact with the air. Does it drain from a certain height to the sump. If both outlet and inlet are under the water it should not be able to drain (unless it is leaking).

DreadCapn · 11/26/2017, 09:06 PM

I avoid check valves all together because you read so much about them failing or needing to be cleaned all the time, so I would first try putting the end of the 1/4" into an piece of 1/2" slanting into the sump to quiet the water. That's a solution that's too dumb to fail

boobookitty · 11/26/2017, 09:17 PM

My preference would be to avoid shooting water into the sump at all, so I’ll give the check valve a try. Never had one fail on an RODI unit.

Inlet is about 4 inches below sump water level. Outlet is about 4 inches above sump water level.

Gorgok · 11/27/2017, 01:32 AM

Quote:

Originally Posted by boobookitty

Never had one fail on an RODI unit.

In pretty much sterile water... vs the full of life stuff growing everywhere water of the tank.

Check valves in general work great. Lots of things rely on them working all the time, like transmissions (i think i had 11 in mine as i rebuilt it). But most of them probably operate in as clean environments as a rodi. Throw some garbage in the system and they will fail, especially if that garbage likes to build hard things like tube worms.

boobookitty · 11/27/2017, 05:08 AM

We’ll see.

jamie1981 · 11/27/2017, 09:25 PM

Quote:

Originally Posted by Tripod1404

How can the reactor drain? What part of it is in contact with the air. Does it drain from a certain height to the sump. If both outlet and inlet are under the water it should not be able to drain (unless it is leaking).

Exactly a reactor should be a sealed loop, I don't understand why the OP doesn't just do this?

boobookitty · 11/27/2017, 09:49 PM

It’s a basic external Skimz reactor: water pumps into the bottom, open drain at the top flows back into the sump. When the pump is off, the water back siphons through the pump back into the sump.

Tripod1404 · 11/28/2017, 01:01 AM

Quote:

Originally Posted by boobookitty

It’s a basic external Skimz reactor: water pumps into the bottom, open drain at the top flows back into the sump. When the pump is off, the water back siphons through the pump back into the sump.

You can add an extender hose from the reactors outlet to below the water line in the sump. If you do this, both the pump and the outlet hose will be under the water, effectively sealing the reactor and preventing water siphoning back trough the pump. As long as both the inlet and outlet are under the water, it would not matter if reactor is above water.

75mixedreef · 11/28/2017, 01:14 PM

Basically it is like taking a cup underwater then turning it upside down and lifting the cup out of the water but not so much as to have the opening above water. The cup will stay filled because there is no air to replace the water in the cup. Same for the reactor, leave no exposure to air and it will not be able to drain. Plus it will be much quieter when the water does not splash back into the sump.

jamie1981 · 11/28/2017, 07:34 PM

Quote:

Originally Posted by Tripod1404

You can add an extender hose from the reactors outlet to below the water line in the sump. If you do this, both the pump and the outlet hose will be under the water, effectively sealing the reactor and preventing water siphoning back trough the pump. As long as both the inlet and outlet are under the water, it would not matter if reactor is above water.

Exactly, but I don't think the OP is getting this.

11/21/2017, 01:38 PM	#1
boobookitty Registered Member Join Date: Oct 2002 Location: Los Angeles Posts: 2,340	Back siphon problem So I've set up a reactor through which I run water from the sump. I have a pump in the sump that I have plumbed through the wall of the sump using a bulkhead to the reactor. The problem is that I need the pump to be off half the time, and when it's off I don't want the reactor water draining or siphoning back into the tank. I've tried flapper check valves, but they inevitably fail within a few days or a week and I come back to find the reactor empty. Same thing with the push check valves, although it takes longer. I've tried a solenoid that turns off when the pump turns off, but they don't work that well: they get very hot, and fail sooner or later. How do I plumb this so that I don't have the reactor emptying out when the pump is off? __________________ It's a reeftank thing; you wouldn't understand. Check out my little red house above for pics Current Tank Info: 400G custom Titan tank, 8 x Radion xr30w pro, zeovit, Reef Octopus SRO6000 skimmer, Ecotech MP60, 3 x Neptune Wav

11/21/2017, 02:13 PM	#2
billdogg Registered Member Join Date: Apr 2008 Location: Grove City, Ohio Posts: 10,806	inline ball or gate valves would be the easiest choice. __________________ I'll try to be nice if you try to be smarter! I can't help that I grow older, but you can't make me grow up! Current Tank Info: 120 mixed reef with 40b sump, RO 150 skimmer, AI Sol Blue x 2, and a 60g Frag Tank with 100g rubbermaid sump. 2 x Kessil A360w lights, BM curve 5 skimmer

11/21/2017, 03:00 PM	#3
boobookitty Registered Member Join Date: Oct 2002 Location: Los Angeles Posts: 2,340	Sorry, should have mentioned, the reactor pump goes on and off every 3 hours, so it’s not something I can do manually. __________________ It's a reeftank thing; you wouldn't understand. Check out my little red house above for pics Current Tank Info: 400G custom Titan tank, 8 x Radion xr30w pro, zeovit, Reef Octopus SRO6000 skimmer, Ecotech MP60, 3 x Neptune Wav

11/21/2017, 04:11 PM	#5
boobookitty Registered Member Join Date: Oct 2002 Location: Los Angeles Posts: 2,340	Zeovit. On 3 hours, off 3hours. __________________ It's a reeftank thing; you wouldn't understand. Check out my little red house above for pics Current Tank Info: 400G custom Titan tank, 8 x Radion xr30w pro, zeovit, Reef Octopus SRO6000 skimmer, Ecotech MP60, 3 x Neptune Wav

11/21/2017, 06:16 PM	#7
boobookitty Registered Member Join Date: Oct 2002 Location: Los Angeles Posts: 2,340	The reactor drains into the sump, so placing it below isn’t an option. 3 on/3 off is the standard for a nutrient-high tank, so yeah, I’m looking for plumbing options that will allow the pump to be off for 3 hours at a time without emptying the reactor. __________________ It's a reeftank thing; you wouldn't understand. Check out my little red house above for pics Current Tank Info: 400G custom Titan tank, 8 x Radion xr30w pro, zeovit, Reef Octopus SRO6000 skimmer, Ecotech MP60, 3 x Neptune Wav

11/21/2017, 07:10 PM	#8
Daddi0 Registered Member Join Date: Sep 2017 Location: Redwood City Posts: 1,354	Peristaltic pump? __________________ 2x 65g displays with a 30g cryptic refugium and 30g sump - 55g reef 30g Bio-cube reef - I.M. 30g reef - 45g freshwater

11/22/2017, 01:21 PM	#9
DreadCapn Registered Member Join Date: Sep 2017 Location: Tennessee Posts: 82	Solution in the sister thread, here: http://www.reefcentral.com/forums/sh...98&postcount=7 __________________ 92g corner, 40b sump, 40b refugium Avast Pegleg Skimmer

11/22/2017, 01:43 PM	#10
ca1ore Grizzled & Cynical Join Date: Apr 2006 Location: Stamford, CT Posts: 17,319	Extend the output hose (?) of the reactor to be under the waterline in the sump - then no way for it to drain down. Otherwise a picture would help. __________________ Simon Got back into the hobby ..... planned to keep it simple ..... yeah, right ..... clearly I need a new plan! Pet peeve: anemones host clowns; clowns do not host anemones! Current Tank Info: 450 Reef; 120 refugium; 60 Frag Tank, 30 Introduction tank; multiple QTs

11/26/2017, 08:10 PM	#12
boobookitty Registered Member Join Date: Oct 2002 Location: Los Angeles Posts: 2,340	Update: I used the plumbing arrangement that DreadCapn suggested, and it works great: I basically built a piece that sits in the sump and replaces the internal check valve that has a pipe going up to an elbow, then a tee with an mpt-to-John Guest 1/4” adapter in the middle, then another elbow and a down pipe. The key is to make the end of the 1/4” tube above the water level in the reactor. Allowed me to remove the check valve and the solenoid valve. Only downside is that the water shooting down into the sump is a bit noisy. I have an in-line 1/4” JG Check valve coming Tuesday (same kind used in RODI auto shut offs), and I’ll try that on the end of the 1/4” tube: should block outflowing water but allow incoming air to break the siphon. I’ll update after that. __________________ It's a reeftank thing; you wouldn't understand. Check out my little red house above for pics Current Tank Info: 400G custom Titan tank, 8 x Radion xr30w pro, zeovit, Reef Octopus SRO6000 skimmer, Ecotech MP60, 3 x Neptune Wav

11/26/2017, 09:05 PM	#13
Tripod1404 Registered Member Join Date: Mar 2016 Posts: 1,821	How can the reactor drain? What part of it is in contact with the air. Does it drain from a certain height to the sump. If both outlet and inlet are under the water it should not be able to drain (unless it is leaking).

11/26/2017, 09:06 PM	#14
DreadCapn Registered Member Join Date: Sep 2017 Location: Tennessee Posts: 82	I avoid check valves all together because you read so much about them failing or needing to be cleaned all the time, so I would first try putting the end of the 1/4" into an piece of 1/2" slanting into the sump to quiet the water. That's a solution that's too dumb to fail __________________ 92g corner, 40b sump, 40b refugium Avast Pegleg Skimmer

11/26/2017, 09:17 PM	#15
boobookitty Registered Member Join Date: Oct 2002 Location: Los Angeles Posts: 2,340	My preference would be to avoid shooting water into the sump at all, so I’ll give the check valve a try. Never had one fail on an RODI unit. Inlet is about 4 inches below sump water level. Outlet is about 4 inches above sump water level. __________________ It's a reeftank thing; you wouldn't understand. Check out my little red house above for pics Current Tank Info: 400G custom Titan tank, 8 x Radion xr30w pro, zeovit, Reef Octopus SRO6000 skimmer, Ecotech MP60, 3 x Neptune Wav

11/27/2017, 05:08 AM	#17
boobookitty Registered Member Join Date: Oct 2002 Location: Los Angeles Posts: 2,340	We’ll see. __________________ It's a reeftank thing; you wouldn't understand. Check out my little red house above for pics Current Tank Info: 400G custom Titan tank, 8 x Radion xr30w pro, zeovit, Reef Octopus SRO6000 skimmer, Ecotech MP60, 3 x Neptune Wav

11/27/2017, 09:49 PM	#19
boobookitty Registered Member Join Date: Oct 2002 Location: Los Angeles Posts: 2,340	It’s a basic external Skimz reactor: water pumps into the bottom, open drain at the top flows back into the sump. When the pump is off, the water back siphons through the pump back into the sump. __________________ It's a reeftank thing; you wouldn't understand. Check out my little red house above for pics Current Tank Info: 400G custom Titan tank, 8 x Radion xr30w pro, zeovit, Reef Octopus SRO6000 skimmer, Ecotech MP60, 3 x Neptune Wav

11/28/2017, 01:14 PM	#21
75mixedreef Registered Member Join Date: Feb 2016 Posts: 255	Basically it is like taking a cup underwater then turning it upside down and lifting the cup out of the water but not so much as to have the opening above water. The cup will stay filled because there is no air to replace the water in the cup. Same for the reactor, leave no exposure to air and it will not be able to drain. Plus it will be much quieter when the water does not splash back into the sump.