Power failure safe sump?

[carlos413]

I have a sumpless 55 gallon reef aquarium. I have always been interested in setting up a sump/refuge. My concern is that in the event I have a power failure, my aquarium water will spill over from the return back in to my sump causing a flood. What can I do to eliminate this risk?

 

[al&burke]

A properly designed sump will not overflow, basically the most reliable type is with an internal overflow box. The tank is drilled at the top - on my sumps I have two drains per overflow box, one as a working back up. Also I have strainers on them. Your returns are either spray bars or a lot of people use lock line, the tank will only drain to the highest hole on your return, once it hits that the siphon is stopped. Your sump/fuge should be designed in a way that the baffles control the height of the water in the sump/fuge, this height is also dependant on the type of skimmer you are planning to use. So saying that your sump should have at least 4 inches above the highest working baffle (where the water flows over). Once the power goes off the overflow drains to the bottom of the teeth (mine are designed to be at the same elevation as the trim on the tank) and the return stops draining once the siphon is broken with the highest hole. Unless you have a large footage of drain and return lines and dependent on the size your sump should not rise more than a couple of inches. Hope this helps.

 

[carlos413]

this helps alot. I got some more research to do, I get the general Idea.

 

[al&burke]

No problem check out Melve's Reef

 

[beaslbob]

An overflow functions like the little hole at the top of your sink. Stopper the drain and the water fills the sink then starts overflowing in that hole. turn the water off and the water goes to the bottom of that hole and stops. turn the water back on and it stops running down the little hole again.
Setting up a sump and overflow is similiar.
get it running normally then turn the power off. It will drain for awhile then stop. Turn the power back on and normal operation should return.,
a final test is to "fail" the overflow itself. break siphon, plug up whatever. the sump should run dry before upper tank floods.
I reccommend you setup a test setup with perhaps some old tanks, plastic containers a pump, and some pvc. Play with it until you get it working. Much better to screw up on the driveway then the livingroom.
A cheapie overflow can be made from pvc. see:
https://forums.saltwaterfish.com/forum/thread/370270/the-beaslbob-trap-s
my .02

 

[flower]

Quote:
Originally Posted by beaslbob http:///forum/thread/385360/power-failure-safe-sump#post_3379028
the sump should run dry before upper tank floods.

I am not a sump expert by any definition. But I just don’t see how this is possible, since the tank is filled to the capacity to begin with. (I'm sure you didn't mean it like it says)
My sump is about ¾ full…. allowing the extra water from the overflow to drain off when power is off, when power is restored the return pumps the water from the sump back to the main tank…once the overflow edge is covered in water it drains back to the sump….but for the sump to run dry before the main tank overflows is impossible.
There is a small hole just below the water line on the return hose from the sump to break the siphon and prevent an overflow in the sump when power is off.

 

[saxman]

It IS possible for your pump to flood your tank assuming your O/F (or standpipe) breaks siphon while the power is still on. Of course, this is dependent upon the water level in your tank (controlled by the teeth placement on your O/F) as well as the water level in your pump bay. However, IME, this has never happened to me, and if you run dual standpipes, should never, EVER happen.
As mentioned, it's important to set you water level in the sump so the residual water in your lines as well as the relationship of your tank level vs. your O/F "skim height" and the placement of your returns (siphon break holes are a must). Once you have the "magic" level, take a sharpie and draw a "fill to here" line on the side of your pump bay. This line will also help you know how much evap. you're getting, and you simply add top-up water to the pump bay to the line.

 

[scsinet]

Quote:
Originally Posted by Flower http:///forum/thread/385360/power-failure-safe-sump#post_3379067
I am not a sump expert by any definition. But I just don’t see how this is possible, since the tank is filled to the capacity to begin with. (I'm sure you didn't mean it like it says)
I think what he's talking about is in the event of a drain failure. Many people who use siphon overflows - as opposed to gravity overflows - are at particular risk of this. When using siphon overflows, considerable system design work must be done to ensure that flooding cannot happen.
I used to use CPR and LifeReef CSOs on all of the tanks with sumps that I had. If the siphon in the overflow breaks, depending on the sump's capacity, it's fill level, and the water level setting on the overflow, enough water can be present to overflow the tank, but in a properly designed system, this won't happen.
Nevertheless, I got tired of the headaches and close calls with CSOs, and have switched to gravity overflows all around. I just don't trust siphon overflows. I always had to watch for an air bubble in the U-Tube or for an aqualifter failure that goes unnoticed too long... too many close calls.

 

[flower]

Quote:
Originally Posted by SCSInet http:///forum/thread/385360/power-failure-safe-sump#post_3379140
I think what he's talking about is in the event of a drain failure. Many people who use siphon overflows - as opposed to gravity overflows - are at particular risk of this. When using siphon overflows, considerable system design work must be done to ensure that flooding cannot happen.
I used to use CPR and LifeReef CSOs on all of the tanks with sumps that I had. If the siphon in the overflow breaks, depending on the sump's capacity, it's fill level, and the water level setting on the overflow, enough water can be present to overflow the tank, but in a properly designed system, this won't happen.
Nevertheless, I got tired of the headaches and close calls with CSOs, and have switched to gravity overflows all around. I just don't trust siphon overflows. I always had to watch for an air bubble in the U-Tube or for an aqualifter failure that goes unnoticed too long... too many close calls.
Wait...wait...wait. I understand overflowing a sump, but Beaslbob said that before the top tank could overflow.. the sump would run dry. The top tank is already full to capasity if any mess up of the drain on an overflow were to happen, the top will overflow in a few moments and it wouldn't take much water to do so.
It sounded like Beaslbob was saying the top tank is safe and the sump would run dry before the top tank could even be in danger of overflowing. OR did I miss something

 

[2quills]

Quote:
Originally Posted by Flower http:///forum/thread/385360/power-failure-safe-sump#post_3379158
Wait...wait...wait. I understand overflowing a sump, but Beaslbob said that before the top tank could overflow.. the sump would run dry. The top tank is already full to capasity if any mess up of the drain on an overflow were to happen, the top will overflow in a few moments and it wouldn't take much water to do so.
It sounded like Beaslbob was saying the top tank is safe and the sump would run dry before the top tank could even be in danger of overflowing. OR did I miss something

This is all speculation on my part since only beaslbob knows what he truely meant...but I think he was refering to the fact that if the overflow lost syphon/quit draining than the pump would pump the return chamber dry before the display tank would have a chance to overflow. But this would actually depend on the size of the return chamber and or if you're running an ATO. Otherwise it would be impossible to drain the entire sump dry. If you were using something like a plastic tote and didn't have any baffles seperating your return pump from everything else then that could be another story.

 

[scsinet]

Quote:
Originally Posted by 2Quills http:///forum/thread/385360/power-failure-safe-sump#post_3379164
This is all speculation on my part since only beaslbob knows what he truely meant...but I think he was refering to the fact that if the overflow lost syphon/quit draining than the pump would pump the return chamber dry before the display tank would have a chance to overflow. But this would actually depend on the size of the return chamber and or if you're running an ATO. Otherwise it would be impossible to drain the entire sump dry. If you were using something like a plastic tote and didn't have any baffles seperating your return pump from everything else then that could be another story.
This is what I took away from his statement as well.
That's why I was saying it all comes down to system design. Although the tank is filled "to capacity" there is usually an 2-3 inches between thewater level and the absolute top edge of the tank. That can be quite a bit... if it was a big tank... a 125 with a 2" below top water level, for example, then you have 18 x 72 x 2 = 2,592, divided by 231 = 11.2 gallons of capacity up there. Since all we are really talking about in a sump is the return compartment capacity, that's a pretty big return zone.
That said, some people DO have return zones that big. A big trend from what I've seen today is giant sumps in relation to tank size. Also, smaller tanks... say a 55g, that same 2" is only about 5 gallons. IMO, tanks should be set up to run with their water level just covering the bottom edge of the canopy or the top brace, whichever is lower, so to achieve a "full look" but leaving room for drain failures.
When designing a sump and tank system, you need to consider:
1. The amount of water in the return compartment of the sump at normal operating levels.
2. The "empty" capacity of the return compartment at normal operating levels.
3. The "empty" capacity at the top of the tank
4. The amount of water the tank will drain in a power or pump loss.
All of those values need to "jive" to ensure a flood-proof system.

 

[cipher43]

Quote:
Originally Posted by Flower http:///forum/thread/385360/power-failure-safe-sump#post_3379158
Wait...wait...wait. I understand overflowing a sump, but Beaslbob said that before the top tank could overflow.. the sump would run dry. The top tank is already full to capasity if any mess up of the drain on an overflow were to happen, the top will overflow in a few moments and it wouldn't take much water to do so.
It sounded like Beaslbob was saying the top tank is safe and the sump would run dry before the top tank could even be in danger of overflowing. OR did I miss something

I think he is refering to regular running conditions when the return pump is pumping and the top is draining to the fuge/sump. Under normal conditions the sump will run dry before the top tank could ever overflow. The order of the post was alittle confusing tho.
As for the question at hand i had a problem with the overflow box i had for some time. It wouldnt matter how much space was in my sump it still would run over. I did find out tho that the inside of the overflow box wasnt glued down in the right position so water was leaking in until it was below the complete box. Once i found that out tho and it was glued shut i havent had any problems with mine so long as i dont over fill my sump side.
The best advice i can give you is once you have everything set up with the sump is to shut the power off to your return after it has ran for a little bit and fill the sump to a level that will leave you safe and then plug in your return pump again and once the water is circulating again at an operational level make a mark on the glass of your sump and never over fill above that line.

 

[flower]

Cipher43, My method was very similar to yours. I think it was Monsinour or Al&Burke who told me what to do..Anyway one of them told me to fill the sump to 1 inch over the return pump ..... (have everything connected to a power strip I could turn off with a quick push..just in case)...turn the system on and keep adding water until the sump remains at 1 inch. Turn off all pumps and see how much had drained into the sump with the power off and fill the sump to an acceptable level where it won't overflow with the system stopped. When you return the power, the top tank refills as it should and the sump now has the correct amount of water without any danger of an overflow in a power failure.

Mark the water line and when it drops from evaporation, refill to that line with RO water for top off.

 

[cipher43]

Quote:
Originally Posted by Flower http:///forum/thread/385360/power-failure-safe-sump#post_3379284

Cipher43, My method was very similar to yours. I think it was Monsinour or Al&Burke who told me what to do..Anyway one of them told me to fill the sump to 1 inch over the return pump ..... (have everything connected to a power strip I could turn off with a quick push..just in case)...turn the system on and keep adding water until the sump remains at 1 inch. Turn off all pumps and see how much had drained into the sump with the power off and fill the sump to an acceptable level where it won't overflow with the system stopped. When you return the power, the top tank refills as it should and the sump now has the correct amount of water without any danger of an overflow in a power failure.

Mark the water line and when it drops from evaporation, refill to that line with RO water for top off.