PVC check valve

[ganjero]

are the pvc check valves that they sell at home depot,lowes, etc safe to use? or do they get clogged? is it better to buy one of the clear ones from marinedepot/

Thanks

 

[Palancar]

The ones I've seen at Lowes are spring-loaded. I think they probably restrict flow. I prefer the swing type.

Swing Check Valve

 

[AZDesertRat]

The best advice is no check valve at all. Proper design should not need a check valve as they are mechanical devices prone to failure.

 

[ganjero]

well my seaswirl will syphon water back, that's why I'm looking for a check valve. Unless there is another way to set the seaswril to prevent syphoning.

 

[SDguy]

Most people just drill a small hole in their return plumbing right below the water surface. It'll suck air, and break the siphon, when the return pump shuts off.

 

[AZDesertRat]

No, most people put their returns so they are just below the surface so they break suction after just a small backsiphonage. Drilled holes also fail, a flake of food, a small snail, some algae....
Put the outlets for the seaswirl just below the surface and always maintain room in the sump to contain a worst case backflow and you never have a problem and you can sleep soundly at night. Why add things that require maintenance when it is human nature to be lazy?
My returns use LocLine and are just below the surface so they don't splash and worst case will flow 3.8 gallons back to my sump. To play it safe I keep 8 gallons of freeboard in my 30G sump at all times and have never had a problem.

 

[SDguy]

<a href=showthread.php?s=&postid=10923637#post10923637 target=_blank>Originally posted</a> by AZDesertRat
No, most people put their returns so they are just below the surface so they break suction after just a small backsiphonage.

No, that would be the best method, and the one I use.

Not the most common though

Lots of things will suffer due to "lazy human nature"... not cleaning your skimmer, not soaking impellers in vinegar. Adding "clean siphon break hole" to a monthly to-do list doesn't seem like a big deal. Though in all fairness, I admittedly am not one that followed that list, unfortunately.

 

[Roy G. Biv]

<a href=showthread.php?s=&postid=10923419#post10923419 target=_blank>Originally posted</a> by AZDesertRat
The best advice is no check valve at all. Proper design should not need a check valve as they are mechanical devices prone to failure.

You must write disclaimers for a living.

Most of the ones at home depot contain metal, springs etc.. I used two different types, one flap type and one wye type. The flap type gave me water hammer. When the flow is shut off, the flap bounces around until the flow is stopped. The wye type just slams shut. The wye type has a top that comes off for cleaning. www.premiumaquatics.com carries most sizes.

 

[AZDesertRat]

No but I have been a water/wastewastewater plant operator and supervisor for almost 34 years and have seen more than my share of check valves fail. Not a pretty sight to say the least especially in a wastewater treatment plant which is basically identical to a reef system.
Do it right the first time and you do not need "crutches" to prop your system up.

 

[ganjero]

I'll look into that cause I'm not drilling a hole in my seaswirl

 

[Playa-1]

Check valves will give you a false sence of security and then it will fail and you will regret it. The best bet is to properly install the equipment in the first place or modify it with a siphon break to help to prevent the problem.