How do I prevent the sump from overflowing if power or pump fails?

Justletters7

New member
It is my understanding that when a return pump or if the power fails that the sump should be able to hold the DT water that is siphoned or drained down to the sump, so are you worried that the water from the DT is to much for the sump to handle?
 

horwitzs

New member
Your sump should be designed with the baffle height low enough that there is still room to hold whatever drains down when the return pump goes off.
Switch off your pump and test it. Make sure the loc line or whatever returns the water in your display doesn't siphon too much water down to the sump also.
 

Ztous

New member
Also your return should be at the surface of your display. Too low and it will siphon water from your DT to your sump. I use a 30 Gallon tank for my sump but it only holds about 20G so that it can handle the pumps stopping.
 

SFish

New member
Drill a small hole on the return line just below the water in the DT. This help minimize the amount of water that can go into the sump.
 

ericarenee

New member
There are a few things to look at with this .. Assuming you have a over flow wehr inside your tank and draining properly ..
------------------------Very Important -----------
Before you start insure that the Return pipe from the pump to the tank is just at or the water level of the tank. its bet to have the top of it just above level so it can suck air and break siphon on power outage . EXPLAINED AT BOTTOM OF THIS TUTORIAL .
--------------------


1.Sump water level
2. Return line from pump in relation to the water height in the tank..

In your sump you should have a return chamber .. The area where your pump is. This chamber usually has baffles to allow less water in this chamber then others..
To check the water volume that over flows from the tank into the sump..

1. With the tank full of water and return pump off .. Remove the water in the sump down to about 2 inches above the Return pump..
2. Start the return pump and let it fill the plumbing and start circulating normally with everything operating..
Note . You may have to add some water to keep the pump from sucking air..If so do this from the water you removed from the sump..
3. once you have found this Minimum water level you can run your return pump and your system works normally . Mark the sump water level at that location and label it Minimum Level..

OK . NOW TO Test a power outage... Have a bucket ready to catch any water in case your sump does over flow..



1... SHUT OFF POWER and watch sump water level..
2. when it stopped Draining back mark this location on your sump..

NOTE HOPEFULLY This will be just below the high baffle before your return pump and not flooding your Skimmer chamber.

3.. If the water level is Below the High baffle before your Return chamber Add some water to where its just below that baffle.. say one inch..

4. Restart the system . Once its running and the water level in your return chamber in the sump has stopped this will be your OPTIMUM RUNNING LEVEL.

5. Mark this location on the sump as MAX WATER LEVEL........

NOTE THIS is what you want your ATO Auto top off or manual if you do not have a ato to stay at....

If all is well at this point

Shut off power again and test one more time.. JUST IN CASE..


NOW if the you have too much water draining down from the tank with power outage..

To correct this you need to look at the return pipe from the pump.. This pipe needs to be Just at the top of the water level in the tank.. If you can not.. then at your return from pump to tank right above the water level on that pipe drill a small hole that you can put a piece of air tubing into and get it water tight.. aim this into the tank but just above the water level insure it only goes 1/4 inch inside the pipe . this will break the siphon and will result in less water drain back.

hope this helps ...

if you post pics of your sump and the return in the tank i can help you further if need be

Erica Renee
 

SFish

New member
You could also use a check valve along with a siphon break. You would have to check and clean it though. They can get stuck.
 

ericarenee

New member
-----------CHECK VALVES ------------------- Not sure why my quite did not work sorry



This is a Accident waiting to happen.. They always fail in a marine environment and are not needed if you have the system setup properly
 

SFish

New member
They are only an accident waiting to happen if they are not maintained and if used with a siphon break even if they do fail it won't flood the sump. In any case nothing fool proof. It's just a way to add redundancy to the system.
 
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ericarenee

New member
They are only an accident waiting to happen if they are not maintained and if used with a siphon break even if they do fail it won't flood the sump. In any case nothing fool proof. It's just a way to add redundancy to the system.

I might have been a bit aggressive with my response to you for that i am sorry.
but if the proper air break and adequate room in the sump is there then why use them.The only thing they really give you is a slower restart time..


So my opinion they are just another part to complicate the process
 

SFish

New member
There is more then one way to run a system. There is nothing wrong with the use of a check valve unless you are solely relying on it. There are very few parts to a check valve so there is really nothing complicated about them. The most common failure is that they can get stuck. Just like anything else they have to be taken apart and cleaned.
 

WillM

New member
I don't know anyone that runs a check valve for anything other than their air pumps. In addition to the other myriad reasons not to use one, I would have major concerns about the materials used to make a large check valve. Brass, copper, etc. have no place in a SW aquarium. This is not a good idea. Is it possible, yes, but things have a way of failing at exactly the wrong times. Go with ericarenee's detailed description of how to do this the correct way that everyone uses with proven and repeatable results (e.g. the laws of gravity and fluid mechanics don't break down, check valves do).
 

heathlindner25

New member
There is more then one way to run a system. There is nothing wrong with the use of a check valve unless you are solely relying on it. There are very few parts to a check valve so there is really nothing complicated about them. The most common failure is that they can get stuck. Just like anything else they have to be taken apart and cleaned.

Check valves are not made for saltwater tanks, I would never install one.
 

Sk8r

Staff member
RC Mod
No check valve. Disaster in the living room when they fail.

OTOH, fill your sump halfway. Turn on the pump. While having FRIEND watch the tank. Then turn off the pump. The draindown should show you how much the tank CAN send down (in most downflows there's a system to prevent more than an inch or so coming down). Add a little water to the sump, then do it all again.

I find that a 3/4 fill on a large enough sump is a pretty good rule. Your skimmer may also have a depth requirement which should be tended to by a support or by slight water drawoff to meet the requirement.

If the depth is correct, you're proof against all power-out conditions.
 

jason2459

Premium Member
Agree, never ever depend on a check valve. I wouldn't add one at all. It provides no failsafe and I'm one to always try and have a failsafe. Having more then one drain setup properly is a failsafe.
 

SFish

New member
I don't know anyone that runs a check valve for anything other than their air pumps. In addition to the other myriad reasons not to use one, I would have major concerns about the materials used to make a large check valve. Brass, copper, etc. have no place in a SW aquarium. This is not a good idea. Is it possible, yes, but things have a way of failing at exactly the wrong times. Go with ericarenee's detailed description of how to do this the correct way that everyone uses with proven and repeatable results (e.g. the laws of gravity and fluid mechanics don't break down, check valves do).

They are made of plastic and I've seen people use them. I'm not saying you have to. There is no right or wrong way.
 
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jason2459

Premium Member
I am thinking another benefit of check valve is u dont have to turn off skimmer if u turn off return pump for feeding.
Actually turning off the pump will help backwash the venturi to help keep it clean.

Same as the return pump. Allowing it to get back washed to me is a plus.


Edit: if someone wants to use one that's fine but do not depend on it to prevent the sump from flooding. It's a flood waiting to happen. I would not use one. The backwash on the pumps is one benifits I've seen over the years. The fish also seem to like it as build up is broken up daily and flung into the tank when the return powers back up. Fish dart around pecking at stuff out of the water.
 
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