Aquarium Overflow Prevention

[BF90GMixedReef]

Dear All,

I'm new to the hobby, but really enjoying it so far. I would appreciate your advice/experience on this matter. I have a 90 gallon Megaflow aquarium (48" x 18" x 24") with a 26 inch Trigger Systems Emerald Sump (20.4 gallons). My question is regarding how to avoid the sump overflowing in case of a power outage. I'm pretty sure that if my sump pump stopped, the water from the aquarium would overflow it before reached a low enough level to stop running to the sump.

Thanks for your help!

 

[BF90GMixedReef]

A

 

[Branespikin]

Put a check valve on your pipe comming out of pump or pick up your return nozzle a bit so it doesnt syphon all that water. The higher up the less water it will suck up.

 

[Danny N]

Install a check valve on your plumbing running out of the pump.

 

[R_C]

Install a check valve on your plumbing running out of the pump.

+1 that is the best way to go. But if not able to just raise your return nozzles. Run a couple of tests and see.

 

[reef_junkie]

Also, aren't the triggers adjustable for baffle height? Deffinitely test the system for powerless floods. That's something you want to do before it happens.

 

[Kungpaoshizi]

Get rid of the sump!
No, the previous answers are spot on. You can also just put a small hole in the return pipe that pumps into the tank. Put it a little under the water and then cut power. It will siphon to the sump until the hole is exposed to air, then it'll break the siphon. (make multiple in case 1 gets plugged)

 

[Mike in CT]

Get rid of the sump!
No, the previous answers are spot on. You can also just put a small hole in the return pipe that pumps into the tank. Put it a little under the water and then cut power. It will siphon to the sump until the hole is exposed to air, then it'll break the siphon. (make multiple in case 1 gets plugged)

++
A siphon break via a hole in the return hoses/pipes is always preferred because mechanical check valve can, and do malfunction.
As long as you keep siphon break holes clear, and high enough, it will never fail.

 

[redfishbluefish]

Please, NO CHECK VALVES. These too will fail. Check valves and saltwater just don't go together.

Simply put in a siphon break. Done!

 

[hawkinsrgk]

I would not depend on a check valve. They can fail. I have a megaflow overflow on two tanks. Going to assume that you are using the megaflow plumbing as well. If that is the case your plumbing has a siphon break at the top of the plumbing. Let me know if you are not using the megaflow kit for the plumbing.

1. When your tank is running, add/remove water until the sump has just enough water so the return pump doesn't draw air into it.
2. Mark where the water line is on your sump. This will be your low water line.
3. Turn off your return pump.
4. Leave the return pump off until the display has finished draining and keep it turned off.
5. Add water to the display until water is at the top in the sump.
6. Turn on return pump and wait until water starts draining again.
7. Mark where the water line is in your sump. This will be your high water line.

As long as water is between the low and high water mark when your pump is running your are ok

 

[hawkinsrgk]

Please, NO CHECK VALVES. These too will fail. Check valves and saltwater just don't go together.

Simply put in a siphon break. Done!

+1 to be more direct about it.

 

[twilliard]

Raise your return jets to just under the water line

 

[jd371]

Get rid of the sump!
No, the previous answers are spot on. You can also just put a small hole in the return pipe that pumps into the tank. Put it a little under the water and then cut power. It will siphon to the sump until the hole is exposed to air, then it'll break the siphon. (make multiple in case 1 gets plugged)

This is exactly what I did. When power shuts off the water reaches about 4 inches from the top of the sump when the siphon break stops it.

 

[AZDesertRat]

No check valves or drilled holes, both are a false sense of security and can and do fail. Besdies that check valves create headloss and reduced flow and drilled holes are annoying as heck and noisy with water jetting out of them. Forget them both, they are not wanted nor needed.

Make sure your standpipe in the megaflow overflow is atll enough that only a small amount of water will flow to the sump before it breaks suction and place your return(s) just slightly under the surface so they too are exposed to atmosphere and the siphon breaks when just a gallon or two of water flows back to the sump.

No check valves to clean and fail when a grain of sand sticks them open and no drilled holes to clean only to have a piece of floating algae plug it up. Neither is foolproof but an air gap is and it is the best form of backflow prevention known to man period.

My display is 100G, the sump is 30G and operates normally with around 18-20 gallons in it since this is where the skimmers works best and when I built my baffles. The overflow box teeth are about 1/2" to 3/4" submerged so the overflow siphon quits there. The two returns are 3/4" below the surface so they too are uncovered and the siphon breaks at a 3/4" drop in the display level.

This 3/4" is 3.5 gallons total (60"L x 18"W x 3/4" H / 231 = 3.5 gallons) so the 30G sump with only 18-20 gallons in it has plenty of room and floods are not in the picture. Water cannot jump uphill and the air gap cannot be defeated. Best method there is and absolutely nothing to clean or maintain.

 

[HiddenUser]

I had to connect a larger tank to my sump to be used as a 'holding' tank in the event of a power outage. No siphon holes, check valves, etc. The power goes out or I stop the main pump for maintenance and I have plenty of room for water to drain.

 

[Mike in CT]

An air gap is great, but I like having my returns under water when I restart my return pump.
I have never noticed noise from my drilled holes.

 

[jd371]

An air gap is great, but I like having my returns under water when I restart my return pump.
I have never noticed noise from my drilled holes.

Me too, and it would be hard for the algae to get stuck on the holes when there is water jetting out of them.

 

[AZDesertRat]

The instant the flow stops the holes start sucking. Bad idea. Algae, food, a small fish, an anemone, a snail, anything can and does block those holes. They are not needed and they can and do fail, all the time. They are a false sense of security. Who do something half baked when you can do it correctly the first time? Its not worth the risk of a flood and there is nothing to clan or maintain with a simple air gap. Worry free and you can sleep soundly at night with no fears of a flood.

 

[TaylorPilot]

I use line-loc fittings, and the exits are only about 3/4 of the way in the water. The water doesn't draw air or make noise. However, the second you cut the pump it breaks the siphon. I will add one further, you are forgetting about your ATO. My general suggestion is to get your system at its running water level. Shut off them pump. When the water level settles in the sump, measure out the tanks L x W x amount of space left from the top of the tank (in inches), then divide by 231. That will give you the MAX size that your ATO can be. So in a worse case senario, you just filled your top off container. It gets stuck open, drains the entire container into your sump, then you have a power outage. Even in that insane scenario, you still wouldn't flood. I agree with @AZDesertRat . Don't use small holes or a check valve to guarantee you sump doesn't leak. If you system doesn't work the way I just suggested above, I would suggest tweaking your system until it does. A flood is a disaster, and should be the primary thing you try to avoid. A properly designed system should have atleast 2 to 3 things that have to fail together before it becomes a possibility.

 

[Sgt Jonny]

Here's a video on that very subject. I hope it helps...