Phobia on Sump

[Fei Miao]

Hi All,

I wonder if my phobia on sump is founded; in event of a power failure while me and my family is away on holidays, will my floor be flooded and the cabinet and furniture wrecked[:0]

Any body have similar experience to share?

[bclee]

If it is an internal overflow sump that should not happen.

This method works like this.

Pump will pump water from sump to tank.
Water will overflow via the internal overflow.
Water flow through filtration back into sump.

So if pump stops or fails, the overflow will stop.

BC

[Fei Miao]

What if it's one of those tanks with the sump on below in the cabinet? Doesn't gravity will cause the water to flow continously down [:0]

[bclee]

No. There is an overflow at the back or corner of the tank. The water OVERFLOWS down into the sump.

BC

[vinz]

Errrrr.... it could happen depending on the set up. If the opening of your output pipe is deep inside your tank, the siphon effect will drain the water into the sump until the water level falls below the opening.

If you are using a u-shaped pipe, I've heard of ppl drilling a hole in the pipe a little below the water level. Then if the pump fails and the water siphons out, it will stop when the water drops below that hole. The catch is the suction at the lower opening will be reduced and you'll have to re-prime the sump after water change.

[AroDon]

Hi Fei Miao

[Power Interuption]
1. Check with your Town Council with regards to any maintenance on Electrical Supply to the area that you are in. Often, the TC will provide you (number to call) with an officer in-charge of your particular block. If there are any maintenance that need to be done, then they will informed the residents via public notice at the designated boards.

[Tank Manufacturer]
2. You can called up the tankmaker who seek advise or any recommendations on ways to prevent the backflow of water, if there are any. Most of the time, IOS is design in such a way that water will stop at certain level... then again like what bro vinz said, it could be possible too.

[vinz]

I think Fei Miao is asking about an external sump setup, not an IOS.

In any case, better to play safe and put in some safeguard as you'll never know when a unplanned power outage will occur.

[AroDon]

[] Ya... A little adjustment to point 2:
In that case, it will be better for all members using external filtration like sump to check with the tank maker... I strongly believe in clearing any doubts, if there are any before indulging to invest in it.

Thanks vinz

[bclee]

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On 7/11/2003 9:39:13 AM

I think Fei Miao is asking about an external sump setup, not an IOS.

In any case, better to play safe and put in some safeguard as you'll never know when a unplanned power outage will occur.
----------------

Yes, external sump uses an overflow system. Water has to be pumped into the tank first for the water to overflow into the overflow box. Then the water will either flow into the sump via a siphon pipe or a tube at the bottom of the overflow box directly into the sump.

In all cases, electrical failure should not cause any problem

BC

[Fei Miao]

Frankly, I don't know there're are a few type nor do I know anything about sump...

What I'm getting at is.... I 'm scouting around for a used 4ft with cabinet and I came across one which seems reasonable(ard $400?). It's with a sump system.

I heard stories .... []

If anyone have pic post to educate me on the different type, I would greatly appreciate that

[bclee]

Here is a simple diagram of a sump with a built-in overflow from a reef tank website.



On the left side is the overflow compartment built into the tank.

First when the pump in the sump below the tank is turned on, the pump will pump the water from the sump into the main tank above.

The overflow compartment is like a surface skimmer. So when water pumped into the main tank, the water will overflow into the compartment. The water will flow into the sump again via the pipe connected to a hole drilled into the bottom of the overflow compartment.

Sometimes, when someone already have a tank without the overflow compartment built-in, he can use an overflow box. Here is a picture of a DIY one.


(A off-the-shelf one will be similar.)

The left side of the diagram shows an overflow box in a tank. The right side is another compartment joined by a siphon pipe. A pipe will connect the outer compartment to the sump below. This method will also rely on water to overflow into the internal box on the left side of the diagram.

So in both cases, it need the pump to be working for water to overflow into the overflow compartment or the overflow box. If the pump stop, the water will stop overflowing and everything stops. No flooding...

BC

[vinz]

BC,

You're assuming that there is an internal overflow before the water siphons or drains into an external sump. Some ppl set up their tanks with overflow sump without an internal overflow.

Fei miao,

You need to check if there is an internal overflow. I.e. a partitioned area inside the tank into which water overflows into. This water is then siphoned or drained from there to the external sump. If there isn't such an area inside the tank, then overflowing during power outage is a problem.

[bclee]

A sump tank must use overflow... there is no other way.

You cannot have a siphon directly into the sump or a pump to pump water into the sump.... because you will never get the input into the sump exactly = output.

Input > output.... sump overflow

Input < output.... main tank overflow

So... only way is overflow system... what the pump pumps into the main tank will results in equal amount of water overflowing into the sump. And there is no worry for pump failure in sump design (the under the main tank kind).

BC

[Fei Miao]

Thanks guys! U think I've a better ideal how this works now

[bclee]

Hey! something happened to my friend's sump. His sump overflowed due to power failure!

It is not due to the overflow. It is the siphoning action due to the backflow via the outlet pipe. The pump stopped and the outlet from the pump became a siphon for the water to backflow from the maintank into the sump.

This however can be retified but drilling an extra hole on the outlet pipe just below the waterline. This help to break the siphoning action in case of pump stoppage. When the waterline lower to the hole that was drilled, it will suck in air and the siphoning action will stop.

The other way is to have the outlet pipe above the waterline.

BC

[Daz]

maybe you can consider the WC method. Once your sump reaches a certain level, the valve will close and no more water will go into the sump.

Dun ask me how it can be done cause never try before, just a thought as I am helping my friend to design his tank & sump system.

[bclee]

Daz, the issue here is not about regulating the flow into the sump. The overflow into the sump is self regulating.

The problem is the backflow via the pump outlet.

BC

[Daz]

My apologies

[bclee]

Hey, no apologies needed. Everyone is entitled to post their views. It is good to put up your inovations. We learn a lot from one another this way.

BC