Sump Filter Probs

[Adrian09]

Just a question about sump filters.

Whenever i turn off power to the pump, the inlet pipe siphons water back into the sump.

This isnt too much of a prob in the event of a water change, but what happens during a power outage or something similar??

is there a valve or something which one can place in the pipe so that water will not run back?

thanks

adrian

[BaZ]

When the power goes off you should get the same result as when you turn off the power to the pump for a water change.

If that's fine, why worry about a blackout?

If there's something else going wrong, let us know. But I cannot see the point of installing a valve unless your sump is overflowing (which it should also do during a water change then).

[catcher]

Adrian,

Is the return pipe from the pump to tank going into the water a fair depth?

I'm guessing what your talking about is when the power goes off and the water syphons back to the sump it's filling the sump with more water than it can handle and overflows, yeah?

If so, all you need do is drill a small hole (3mm) in the return pipe to the tank just below where normal operating water level is in the tank, remember I'm talking about up in the tank not in the sump. Then when the power goes off and the syphon starts the drain-back it only drains to the hole as it breaks the syphon effect by letting air in behind the water. No more overflow.

I hope this is what your getting at anyway.

cheers

glenn

[BaZ]

Is the return pipe from the pump to tank going into the water a fair depth?

I'm guessing what your talking about is when the power goes off and the water syphons back to the sump it's filling the sump with more water than it can handle and overflows, yeah?

I first thought of this too, but yet he says turning the pump off for a water change is fine.

If his return pipe is draining the tank in a blackout, it should also drain the tank any other time the pump is turned off.

[bishop]

Without some method to stop the syphon you run the risk of draining the tank during a power outage.

I built myself an overflow box whch ensures the water never drops below the overflow box outlet. You also never lose the prime when you do a water change.

Does not allow you to drain water through the outlet for water changes though.

[Guest african-au]

my understanding is that you are running a mini-reef system

if so keep water level to the point that when it does return to your sump it cannot overflow!

that way if there is a blackout everything is ok!

the only way you can overflow your sump is by adding too much water in your tank otherwise its quite normal for the water to flow back into your sump

thats if you have a weir offcourse!

chris

[BaZ]

Are you guys getting something from his post that I am stupidly missing?

Whenever i turn off power to the pump, the inlet pipe siphons water back into the sump.

This isnt too much of a prob in the event of a water change, but what happens during a power outage or something similar??

I fail to understand the issue at hand. If he can turn the pump off to do a water change and the sump does not overflow, how does a blackout differ?

The advice given by you all is great advice for someone who has a sump which always overflows, but his doesn't from what I can see.

If I am missing something quite obvious would someone please slap me in the face and point it out?

[duck]

bit off topic but still related ... everytime i turn my pump on after water change i get this yucky white/yellowish crap. it must be from the hose/pipe ...is there any way to get rid off them for good?

[catcher]

No, your right Baz, I sort of jumped the gun when I read it more closely. The situation described does seem a little strange.

glenn

Oh Duck,

Cleaning goop out of the supply pipe is easily done with a pipe cleaning brush tied to some heavy gauge nylon cord. Feed the cord through the pipe from one end to the other and pull the pipe cleaner through.You'll be supprised how much crap comes out.

glenn

[Adrian09]

when I do a water change i take the inlet tube out of the water to stop the syphoning effect

initially the inlet was almost half way down in the tank so that was a lot of water

i changed that and now it is maybe 3 inches into the water but being a 6x2x2 it still fills the sump filter a little too much

sorry for the misunderstanding

what i meant by it's ok when i do a water change is that I am physically there to stop the problem

but in the event of a power outtage there is a good chance i am not there!!

[Ash]

Drill the hole in the return pipe just below tank water level & then cut power to the pump. Do it multiple times as well if you are paranoid.

[catcher]

Hi Adrian,

That explains it then, I know where Baz was coming from and I sort of lucky and second guessed what you meant. My inital response still stands, just as Ash has suggested as well. Drill a hole at surface level or just below then the only water that will get back to the sump is what comes from the returns.

Remember, when you refill after a water change, fill via the main tank and allow that water to overflow into the sump to whatever you think to be your comfortable or safe level.

glenn

[BaZ]

Yep looks like Glenn guessed it right

We should all remember that the power can go out at ANY time for any number of reasons.

Those of us running sumps should make sure that the sump is big enough to hold any water which flows or syphons down from the tank without the need for us to intervene.

Glenn not only guessed the right question, but also gave a good answer. Just make sure the hole is big enough to effectively break the syphon, and keep an eye on it to make sure it does not get blocked with algae or gunk of any kind.

Whenever I do a waterchange on my sumped tank, I always make sure I allow the tank to drain to the sump fully (as far as it would go in a blackout) because I like to regularly check that things will be fine in a blackout. I never like to set and forget anything, because I think my wife would be particularly scary should she find the contents of my tank on her loungeroom floor

[Downunder]

Hey guys,

hope I'm reading it right too. I've got a sump set up as well and have a check valve on my return to the tank ( flapper type) this stops any reverse flow. i've also put a ball valve in the return line so if the pump is off for a while or I want to remove it I just close it. This way you don't need to drill holes in your hose and just need to check it every now and again to make sure it's sealing right. Hope this helps

[Adrian09]

thanks everyone for the replies

i will test the hole in the pipe method and check that it works.

hopefully it will give me some peace of mind

my sump should be ok now that i modified the depth of the inlet tube also but just incase!

Downunder, where did u get that check valve from? sounds like a good backup plan.

[Downunder]

Sorry it's been a a couple of days. Got the Check valve from a plumbing supplies shop (Brass type), but Mitre 10 or Bunnings sell one (plastic type) that has a spring in it. You just have to remove the spring and hey presto. good luck,

Wayne

[Lv426]

My setup sounds exactly like yours except I gather that your return pipe goes deeper into the water than mine. Therefore if say the power goes out it will drain all the way to just below the spray bar....causing overflow of the sump..right? I have a 2ft sump running a 4x2x2, with my return spray bar just below the surface. When I switch off for water change it drains back to the sump only a small amount of water, nowhere near enough to flood. What water level do you keep your sump at? I keep mine just below the bottom layer of bio balls. I think you have two solutions either get a valve (which you have) or raise the height of the return spray bar relative to the tank.

bit off topic but still related ... everytime i turn my pump on after water change i get this yucky white/yellowish crap. it must be from the hose/pipe ...is there any way to get rid off them for good? mad.gif

get a small length of hose, raise the water level with tank water then siphon the goop from the bottom. Do this twice and very little disturbed gunk will return to your tank..

[CThompson]

When you install/design a sump, it should accommodate the runoff from the tank to the sump to enable the sump’s capacity to hold this excess water.

As Glen has mentioned with his tube insert idea, this may work, but it will still be limited to some extent as how well it works, will be dictated by how much suction there is (how far the water falls to the sump), and how big the tube you insert to break the siphon effect. If one tube does not work, try a second, then third until enough air is introduce to break the siphon effect. Alternatively you could insert a bigger pipe.

In regards to check valves. If it is designed to have a spring, then it needs a spring, by taking the spring out the valve may not work. Remember we are talking about water all over the floor here if the sump overflows, so it has to work 100%. Aquasonic has a blue coloured one way valve which has not been designed to not need a spring.

Make sure when you install a one way valve, you match the internal diameter of the valve with the internal diameter of your plumbing. Also, if you use a one way valve with a spring, be aware that you will reduce you water flow by the equal amount of pressure that it takes the water to push agains/past the spring.

Also be aware that if you use a one way valve make sure you install it in a vertical position, and have it at the other end of the pipe away from the water exiting from the tank, so there is as much pressure as you can put on the valve to close it up.

Remember too, if your returning tank water is a bit dirty, and it gets caught on the closing mechanism of the one way valve, the shut off mechanism in the one way valve will not create a complet seal (it will be closed in a position that will allow water to pass).

The best is to design the sump to hold all the water that runs down to it.

Or raise your return pipe to as high as you can make it, then when it is as high as you can go, and if your sump still overflows, then try Glen’s suggestion of breaking the siphon by inserting a tube.

Craig