wet-dry floods

[ebosshard]

Anyone have any solutions for preventing floods from wet-dry's?

Have had two of them from knocking off electricity and putting in rock. Pump stops sending water back to tank, wet-dry overflows, and a flood ensues.

Thanks for any secrets!

 

[ChrisRD]

You'll need to run the water level lower in the sump.

Measure how far the main tank drains down (from the regular operating water level) when the pump stops. Then, knowing the dimensions of the tank and this number, you can calculate how many gallons of capacity you need in the sump to handle the additional water without overflowing.

By knowing the extra volume you have to handle, and the dimensions of the sump, you can then figure out what level you need to run the water in the sump to leave enough extra storage capacity so it won't overflow.

 

[ebosshard]

1-so in theory if i run the water low enough in the sump (the wet-dry i assume you mean), when the pump turns off the amount of water that runs out of the back of the tank down into the sump should just fill that up and not overflow? it is ok to run the water that low and have hardly any of the bioballs in the water?

2-It seemed like last night the pump (when unplugged) ended up acting like a siphon and was pulling water back into the tank, is that possible?

 

[PeeJ]

which wet dry do you have?

yes it is possible to siphon water back into your sump...just drill hole in your return right at the water line to break the siphon.

 

[ebosshard]

so if i drill a hole below the water line from the pump to the tank it will no longer siphon backwords from the tank? but will it still send water to the tank from the pump?

wet-dry is a custom job for my 220g tank. two compartments: one side is input (filter media and then bioballs), other side is where pump sits that sends water back up to tank).

thanks

 

[PeeJ]

yes everything will be fine...just make sure the hole sits just under the water. so when then tank drains a little, it will suck air and stop the siphon.

as far as my wet dry is concerned, none of the bio balls are submerged. they sit under a drip tray. the water line for the wet dry is right under the egg crate the bio balls sit on

 

[ChrisRD]

1-so in theory if i run the water low enough in the sump (the wet-dry i assume you mean), when the pump turns off the amount of water that runs out of the back of the tank down into the sump should just fill that up and not overflow? it is ok to run the water that low and have hardly any of the bioballs in the water?

Yes, and yes. As long as the bioballs have tank water flowing over them they are going to work - they really don't have to be submerged. That is the purpose of the drip plate/spray bar - to distribute tank water over all of the media allowing it to trickle through and collect in the sump.

2-It seemed like last night the pump (when unplugged) ended up acting like a siphon and was pulling water back into the tank, is that possible?

I'm sure you've noticed that when the pump is first powered-off there will still be a syphon in your drain line from the main tank down to the sump of the wet/dry. It will pull water from the tank until it sucks in enough air to break the syphon. The same effect can happen through your return line/return pump. Whichever opening is lower will determine how far the tank drains down. In other words, don't submerge your return line deep in the tank unless you drill a syphon-break hole in the line, somewhere close to the surface.

 

[ChrisRD]

I guess PeeJ beat me to it...LOL

 

[PeeJ]

heheheheh....its a good thing i have a dedicated oc-3 line to my house haha just kidding

 

[ebosshard]

So I am to keep the water level below the bio balls (but obviously above the top of the pump?)

 

[ChrisRD]

That would be a good start. Or you could calculate the level you can run (as mentioned above).