Check Valves

[bangbangkhan]

Are check valves really necessary for the return pipe? or they are redundant?

Thanks

 

[wontonflip]

Not redundant....VERY useful. If you have a built in overflow, it also helps to drill a hole on the return nozzle just below the water line. Read this heart breaking thread from one of our old reefers -- he did have a check valve, however, he hadn't cleaned it in a while, and one day the power failed, and it was stuck on the open position, and he didn't have his nozzle drilled to let air in to prevent suction. This happened:

https://www.livingreefs.com/rains-pours-t28609.html

 

[bangbangkhan]

But if your return nozzle is just 1 inch below the tank's top edge then it shouldn't flood more than a couple of inches of the display tank's water?

 

[FishyReef]

Yes, but often the sump is smaller than the display so a couple of inches of display tank water could be several gallons, while the capacity of the sump may not be able to hold that much back flow. If you go without a check valve then make sure your sump can handle the amount of back flow before the siphon breaks. I have my return nozzle right at the water line so when my pump shuts off very little flows backwards before the siphon is broken.

 

[wontonflip]

+1 fish. I need to drill mine....I've got a check valve, but I always remember dcan's disaster. My tank's 125 and has 2 return nozzles. Sometimes, when I do major maintenance like cleaning my return pump and check valve, I forget to point the nozzles up, so when I unhook the check valve, water just comes gushing down from the dt lol

 

[bangbangkhan]

Yes, but often the sump is smaller than the display so a couple of inches of display tank water could be several gallons, while the capacity of the sump may not be able to hold that much back flow. If you go without a check valve then make sure your sump can handle the amount of back flow before the siphon breaks. I have my return nozzle right at the water line so when my pump shuts off very little flows backwards before the siphon is broken.

I am installing it on a 90 gallon with a 3/4 return line and the sump would be 30 gallon.

 

[salt_for_brains]

I don't use check valves but I do have holes drilled to break siphon.

 

[Ted]

I dont use a check valve. I have two holes drilled.

 

[bangbangkhan]

Where exactly whould I drill on the return line?

 

[salt_for_brains]

I drilled mine in both return tubes(two small holes each) just below my water line.

 

[Ted]

I have one return line, drilled two hole just below the water line also. I would say about a 1/4 of a inch in the water.

 

[bangbangkhan]

Thanks!

 

[FishyReef]

Make sure to aim the drill upwards so that water flows downwards through the holes. i neglected to do so and water sprayed at my ceiling! I also think I made my holes too small.

 

[bangbangkhan]

Make sure to aim the drill upwards so that water flows downwards through the holes. i neglected to do so and water sprayed at my ceiling! I also think I made my holes too small.

Lol...I was wondering about that.

 

[Ted]

the water in mine shoot out straight to the sides.