Check value before gate valve? Need answer asap

[Dr Colliebreath]

I don't think it matters whether it is before or after your gate valve. It does need to be after the pump.

As you will need to remove the check valve for maintenance, I would put it where it is most convenient to you. I would say pump >> check valve >> gate valve >> bulkhead. This way, you can shut off the gate valve and prevent backflow into the sump when you remove the check valve to clean it. Given you will clean it only a 3-4 times per year hopefully), you could use the other order and just live with the extra water in the sump occasionally. Put true unions on either side of the check valve so you can remove it for cleaning.

 

[Maivortex]

The op asked wht sequence should the check valve be in, NOT if he needs a check valve. But since the goal of this thread has been changed by posters other than the OP IMO the necessity of the check valve depends on how someone maintains there tank. The OP needs to prevent the skimmer from overflowing. I like having a check valve to keep more water in the display for when im doing a WC and siphoning out detritus. Relying on gravity to siphon water out of the sump is problematic unles u have a python.

 

[r-balljunkie]

install it however you want....i'd do it with the notion you will be removing it in a year after it fails....arrange it so its cheaper to remove like using unions instead of having to cut out all of your plumbing and cannot reuse the gate valve.

 

[Boboli]

Pump -> check valve -> gate valve -> bulkhead
Then when you have to replace the check valve you can shut the gate valve and not drain aquarium water .

 

[igadget56]

When I restart the pump I am pushing 40 gpm through a 1.5" x 14'0 long riser line. This creates massive bubbles that push into my DT. The check valve keeps my riser full and restart is very smooth. The check valve causes no problems as my sump is designed to handle backflow should it fail. Also came in handy when my ATO overfilled my sump and I lost power to my pump. As long as your sump is designed properly and the check valve is added as an "extra" bonus is will cause no problems and will add convenience OP is looking for.

BTW.. What happens when a snail is covering that 1/4" pinhole?

Put 4 holes in and check once a week.If you're lucky enough to get 4 snails to cover 4 holes in one week, go buy some lottery tickets!!

 

[robertcedgar]

There is much good information here, however, I would configure as follows:

Pump -> check valve -> gate valve -> bulkhead

In this way, if you "tee" off of your return for other equipment, your check valve will always be the lowest and prevent potential siphoning. Of course, you don't want to rely entirely on a check valve as they do fail at times. Redundancy is the key. To that end, try a siphon break (small holes in the return, if you can....setup will dictate), and placing your return just below the display water's surface in the rare event that all else fails. That, in and of itself will break a siphoning episode. Hope that helps......