Do I really need a check valve on return lines

dreamcatcherr9 · May 30, 2020

Do I really need to use check valves?

If my sump is large enough to handle the back flow of water? Using 2 DC pumps....

The “right” answer in know is yes, but I’m really trying to avoid them if I can. Added plumbing. Possible failed point in future. Difficulty servicing.

Does anyone NOT use them?

And if you say yes; type, style, brand please?

F i s h y · May 30, 2020

The sump on the system i have been helping with holds everything that back siphons. I dont think many people use them. I do not use them

leepink23 · May 30, 2020

If your sump can handle the volume then no not needed. I use them but definitely not required

mike550 · May 30, 2020

dreamcatcherr9 said:
Do I really need to use check valves?

If my sump is large enough to handle the back flow of water? Using 2 DC pumps....

The “right” answer in know is yes, but I’m really trying to avoid them if I can. Added plumbing. Possible failed point in future. Difficulty servicing.

Does anyone NOT use them?

And if you say yes; type, style, brand please?

For what it's worth, I don't have check valves. When I turn off my return pumps to the extent that the water drains back into the sump I still have capacity. It seems like the better practice is to not rely on check valves but rather size the sump volume, etc. properly.

dwest · May 30, 2020

No, don’t use them. Another failure point IMO.

92Miata · May 30, 2020

mike550 said:
For what it's worth, I don't have check valves. When I turn off my return pumps to the extent that the water drains back into the sump I still have capacity. It seems like the better practice is to not rely on check valves but rather size the sump volume, etc. properly.

This.
Mechanical devices exposed to salt water fail. Its not a question of if, but when. You're better off without one.

Doctorgori · May 30, 2020

just in case your survey requires more date...no

GaryE · May 30, 2020

I put a syphon break in my return line. I keep my water level in my DT right at or just below that hole and never worry. My sump never fills to even the point where my skimmer cup attached to my FC80 skimmer.still about three inches left in the sump before carpet gets wet.

ca1ore · May 30, 2020

Don’t think the ‘right’ answer actually is yes. I think most experienced reefers have concluded that checks really don’t work all that well, and are just one more thing to forget to maintain.

jman930 · May 30, 2020

I have a different experience. I don’t have a massive sump so I put check valves on my dual return lines. Saved my bacon on multiple power outages over the years.
Best to plan for the worst and hope for the best. If you have room for a big sump to handle to water good. If you have a check valve too then that’s better. If you keep your returns pointed toward the surface to minimize the amount of water that could get siphoned down along with the rest then that is your best solution.

Idoc · May 30, 2020

dreamcatcherr9 said:
Do I really need to use check valves?

If my sump is large enough to handle the back flow of water? Using 2 DC pumps....

The “right” answer in know is yes, but I’m really trying to avoid them if I can. Added plumbing. Possible failed point in future. Difficulty servicing.

Does anyone NOT use them?

And if you say yes; type, style, brand please?

I don't think the "right" answer would be "yes" for check-valves. If you have enough space in your sump to handle the backflow of water when the pumps shut off, then you are fine. The checkvalve just adds another complication into the system...and reduces your flow from the pump.

Diyreef8401 · May 30, 2020

I use siphon stoppers. Kinda bulky but they work.

RocketEngineer · May 30, 2020

Check valves require the mechanism to seal in order to work. However, microbes and other critters such as tube worms and sponges grow just about anywhere, including on valve sealing surfaces. Given this, check valves are much more likely to leak if not outright fail. I’ve never used one and never will.

GaryE · May 30, 2020

RocketEngineer said:
Check valves require the mechanism to seal in order to work. However, microbes and other critters such as tube worms and sponges grow just about anywhere, including on valve sealing surfaces. Given this, check valves are much more likely to leak if not outright fail. I’ve never used one and never will.

Plus an 1/8 inch hole in your return line at the water line is free and foolproof.

RocketEngineer · May 30, 2020

GaryE said:
Plus an 1/8 inch hole in your return line at the water line is free and foolproof.

I respectfully disagree for the same reason: crud growth. I use wide return nozzles placed at the surface because the width minimizes the chance of something small blocking air from getting in. With 3” of nozzle, air will get in somewhere.

GaryE · May 31, 2020

I can clean that crud growth with a tooth pick. As my water line is typically a half inch below my siphon break, it's pretty simple to see if it's closed and clean it.