Gotta ask a stupid question; 2 different sumps

[sashimimaster]

Ok, so I'm supposed to be fairly intelligent but I can't believe I still have to ask this. I think I know the answer but here goes anyway.

I'm planning on having two sumps for my monster tank. They will have different heights. They will both draw water from an overflow and return via pumps, both the same size. One is shorter than the other because of various filter media and an algae scrubber.

My question is this. Will there be a problem with the water overflowing the shorter sump since the water level of the larger one is higher? Since they are both connected to the main tank doesn't the water level equalize between them?

 

[Burko]

"Since they are both connected to the main tank doesn't the water level equalize between them? "

No. The two sumps must be connected to each other.

If you need(?) different water depths in them then lower or raise one sump, connect and 'viaola'...

 

[Burko]

"My question is this. Will there be a problem with the water overflowing the shorter sump since the water level of the larger one is higher?"

Or to be clearer...

One sump will overflow.

Which one it will be, is more dependent on pump v's overflow differences than the starting height of the water.

 

[boldtogether]

If the lower sump can handle the flow when the returns are off then you are good. If you are using the same overflow and splitting the flow but are restricting the flow to the smaller sump via tubing diameter or a gate valve, then you are good. The problem arises when each sump is fed from the same overflow and the water that flows back into the sump when you turn off the returns(or during a power outage) is more than the smaller sump can "absorb".

If you run check valves on both returns then you are good.

 

[Griller]

The problem arises when each sump is fed from the same overflow and the water that flows back into the sump when you turn off the returns(or during a power outage) is more than the smaller sump can "absorb".

Agreed. 2 sumps make life hard. I'd connect them like burko suggested. You are going to have complicated water movement otherwise. Keep it simple if you can.

 

[livebearerfreak]

why not just do a sump tank/. like a 55 gallon, then you dont have to worry bout any overflowing.

 

[sashimimaster]

"Since they are both connected to the main tank doesn't the water level equalize between them? "

No. The two sumps must be connected to each other.

If you need(?) different water depths in them then lower or raise one sump, connect and 'viaola'...

I need to have two different levels. One sump has a drip tray over wet/dry bio balls and the other has an algae scrubber with a lower water level. If I connect them then the lower one will over flow.

 

[sashimimaster]

I forgot to mention that the overflows are connected and draw water at an equal rate. Since the flow to the sumps is limited by how much the pumps pump back into the main tank I should be good right?

 

[sashimimaster]

If the lower sump can handle the flow when the returns are off then you are good. If you are using the same overflow and splitting the flow but are restricting the flow to the smaller sump via tubing diameter or a gate valve, then you are good. The problem arises when each sump is fed from the same overflow and the water that flows back into the sump when you turn off the returns(or during a power outage) is more than the smaller sump can "absorb".

If you run check valves on both returns then you are good.

When the power is off the flow simply stops going out of the tank so the sumps shouldn't receive any water. I do have check valves in both of the returns.

 

[Pharaoh]

I would do as suggested and raise the sump with the lower water level so that the water level is the same height as the other sump. By lifting the entire sump, you can still maintain the lower water level for the scrubber.