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View Full Version : Check Valves in the reef?


kwaters
10/09/2008, 01:00 AM
I was online (duh) searching for some bulkhead parts and came across a site that sold check-valves. Now, I often worry about power failure and overflow of the sump. As a matter of fact, I just built a new tank (14 gallons) to add on to my current sump for my new 110 gallon.

I ask, does anyone have check valves in their system? It seems like a good way to prevent overflow due to power loss.


Kris

silverwolf72
10/09/2008, 01:08 AM
They tend to stick open when you need them to work. Your better off with a sump that can handle the extra volume of water and creating siphon breaks on your returns

miwoodar
10/09/2008, 01:13 AM
silverwolf72 is right. They are not reliable in a reef tank. Growth of sponges, tunicates, vermitid snails, etc will cause them to fail.

nikon187
10/09/2008, 03:24 AM
all very true. if running one it is advised to install a union on either end so you can clean them, i would also change them yearly. Best method is to have room for the back siphon until it breaks as mentioned above

modd77
10/09/2008, 05:49 AM
I use a swing check valve from marine depot on my tank and it works great. Had it on for about a year now. Does what it is supposed to do.

EnderG60
10/09/2008, 06:03 AM
just make sure its higher up then the highest water level in the sump. and only use the clear type sold at marine depot(dont have to get it there just that kind)

calkulon
10/09/2008, 06:28 AM
I have been using a swing arm check valve on my tank for about ten years with no issues. Living in central Florida, between thunder storms and hurricanes, power failures are very common. I have a tee installed just ahead of the lockline tank return. The check valve is screwed backwards into this tee. The tank return water holds the valve closed and when flow stops it is opened by the vacuum of the falling water. With the valve being above the surface of the water, it is very easy to unscrew by hand and clean, takes just a few moments.
One note, when water flow is restarted a little water can shoot from the valve befor it reseals. To avoid water being sprayed about ( murphy says lights for sure) an elbow screwed to the other side of the valve and pointed towards the surface of the water is a good idea.

BeanAnimal
10/09/2008, 07:26 AM
<a href=showthread.php?s=&postid=13512769#post13512769 target=_blank>Originally posted</a> by calkulon
I have been using a swing arm check valve on my tank for about ten years with no issues. You are by far the exception, not the rule. Check valves fail with certain regualrity.

The best advice is to design a system that does not require check valves. A system with NO check valves can can not flood due to a fouled check valve.

psteeleb
10/09/2008, 08:34 AM
I would advise you to design your system to deal with a power off situation and not depend on a check valve or other device taht could fail. Better safe tehn sorry here. Consider your sump volume normal levels & over flow levels, and use anti syphon holes on your return lines to help prevent a main tank drain that would over flow the sump durring a power off situation.

I for one turn power off all the time for feeding, cleaning, killling mojanos' etc. My sump pretty much maxes out with power off so I wish I had set my normal sump level a little lower.

Like Beananimal indicates they will fail, it's just a mater of time (could be a month could be years). I for one don't have any, but if I did I know for certain it would not work as the internals of my pipes have growth on them (dusters, sponges, etc) that would also be on the check valve seat preventing it from sealing properly.

Big Boy69
10/09/2008, 08:49 AM
I use one that you can take apart and clean, with a ball valve right above it. I also have a sump that will hold the extra water.

AZDesertRat
10/09/2008, 08:53 AM
Check valves are a false sense of security and will fail. Its a certainty. You can clean one this moring and have a snail or grain of sand in it this afternoon, no amount of maintenance in the world can prevent it.
The only surefire foolproof method of preventing floods is keeping the returns close to the surface so you have an air gap once the level drops a small easily calculated volume and always maintaing thet much room in your sump at all times.

curthendrix
10/09/2008, 08:56 AM
I installed two check valves in series about 6 inches apart and tested them every week. I never felt overly secure with them but they would both have to fail at the same time for me to have a problem.

miwoodar
10/09/2008, 09:35 AM
It's fine to have them but do not *rely* on them. Design your system so they are not required and if you want to add them, do it. They will reduce your pump output though.

kwaters
10/09/2008, 06:41 PM
Thanks for the responses. I have a sump that I will use from my existing set up, and just built another to help take up that extra volume when the return pump is off. I will attach it to the existing sump (with bulkheads) and it will now be my return.

As stated, I saw these advertised and thought I'd ask! It's always good to get advice from those who have tried it!

PS>>Psteeleb what do you use to rid the yourself of the mojanos?

Kris