reliable check valve?

[reefermike1]

is there such a thing? id like to drill towards the bottom of the tank and run a spraybar as the return.... is there a check valve available that would be up for the task?

[Mako]

I have used the these (http://www.customaquatic.com/estore/control/subctg/~ctg=s_pf-cv-sc/~pctg=s_pf) on a few different systems with good results. Be sure to get the true union version and buy two. Place a ball valve above it so you can easily swap in a cleaned unit as part of your maintenance routine. I usually swapped a clean one in every 3 months.

[Percula9]

I have used a check valve for the last two years 2with no problems. I don't care for spray bars as they clog after time

[kdblove_99]

I would not trust any of them long term

[hodgepodge1983]

I agree with kdblove, I've had & seen figuratively tons fail! Luckily I've built in redundancy; always have a siphon-break somewhere along the line! Mine is about 1/2" below the water line on the return. :)

[Racing1]

It's not if they will fail, But when.....

[AZDesertRat]

No, there are no reliable check valves. An air gap is the only positive foolproof method of backflow protection, and that is not a drilled hole. As long as the return is slightly below the surface you will only backsiphon a small easily calculated amount of water back to your sump. Maintain at least that much room at all times in the sump and you are set. My 100G siphons a max of 3.8 gallons and thats easily contained in my 30G sump.

[dkh0331]

<a href=showthread.php?s=&postid=13782211#post13782211 target=_blank>Originally posted</a> by Racing1
It's not if they will fail, But when.....

X2

[reefermike1]

thanks for all the replies. thought maybe there was a high quality checkvalve available that i hadnt heard of.

[Mako]

Properly maintained the odds of failure are extremely low. I used one the way I described for over 5 years with no failure.

[AZDesertRat]

Proper maintenance really doesn't matter. Maintenance won't keep a grain of sand or snail from defeating it. It does not have to be a catastrophic failure, even a slow leak over an hours time can be disasterous. If there was a reliable one we would have been using them in the water wastewater industry years ago.

[Mako]

Maintenance is everything in this hobby, just as it is in your industry I would imagine. All the equipment we use will fail, at some point, without it.

A grain of sand, or snail, on the discharge end of a pump?? Never seen a snail in the discharge end of any setup I have run or encountered. Intake yes, but discharge? Sand just blows right on by, but if you have sand entering your pump on the intake you have some other problems to worry about.

The thing to watch for is calcium buildup, hence the reason I suggested a spare and regular cleaning.

[mflamb]

Thanks Mako, I'll try one of those.

[AZDesertRat]

Disaster, mark my words. I see small snails inside pumps all the time. In 34 years in the water wasterwater industry I have yet to see a check valve reliable enough for an aquarium. Its just like a miniature wastewater treatment plant and they avoid check valves like the plague in WW plants.

[jsc0787]

I've used a nice clear double union flapper in the past. One day I found my sump overflowing....even flappers don't always seat perfectly every time. I'll never use another check valve again.

If you want a return under the water than do it with a closed loop. There is no need to have more flow running through your sump than your protein skimmer can process anyway.