Water level in sump

[jaws7777]

Currently using the jebao dct 1200 on setting 3 which sould be 1331 gph according to the attached pic.

The overflow is a pf1800 rated for 1600 gph.

If i increase flow to the next setting (1553 gph) the water level in the sump drops. Shouldnt it stay the same ? Unless the drain plumbing are creating more restriction to flow than i thought and im not getting the 1600 gph. Using 45's and a couple of unions.

Not a big deal as i intend to keep it on the vurrent setting but was just curious.

 

[esoxlucius]

I've got that very problem at the min. I have a 10 speed pump. Its fine up to setting 7. As soon as i put it on setting 8 the level in the display tank very slowly rises and the compartment in my sump with the pump in goes down. My drain can't cope with the extra volume but in my case, like you, i'm not to concerned because setting 7 is a good turnover for me.

 

[Danh]

The water level in your sump drops because the water level in the main tank raises. It raises based on your overflow weirs and how much water they flow per inch (or whatever measurement) of height.

If you're barely flowing anything, then the water just barely overflows and trickles over the weir. Turn it up and it's flowing a lot more over the weir which can only be accomplished by raising the water level in the tank. A big footprint of a tank requires a lot more volume of water to get the level up enough. Your sump, then has to be able to handle it if the pump stops. All of that water height above the weir will drain in to the sump and stay there.

 

[Danh]

Just found this pic on the net. To the left it looks like the water level is about .5" above the bottom of the weir. Flowing less water, it wouldn't be as high.

 

[millerkid519]

D Danh summed it up perfectly

 

[jaws7777]

D Danh i dont understand though. If i bump the level up to the next setting which is 1531 or something and the overflow is supposedly rated fro 1600 should the level remain constant in the sump ?

 

[millerkid519]

Just found this pic on the net. To the left it looks like the water level is about .5" above the bottom of the weir. Flowing less water, it wouldn't be as high.

No the water level will lower in the sump as more water will be pushed up into the main tank. Yes your overflow is rated for 1600 gph but as the flow threw the weir increases the water level is higher in that tank because the water needs to use more of the height of the weir to flow threw. Your weirs are the bottle neck of a hob overflow
Sorry I ment to tag J jaws7777

 

[jaws7777]

millerkid519 and D Danh makes sense now thanks guys. So it would be safe to say the display would eventually overflow ?

 

[millerkid519]

No it shouldn't overflow it will just need to use more of the height of the weirs to overflow the higher volume of water. I am running 1500 with that same overflow box

 

[jaws7777]

Ok thx guys i wasnt figuring in the weirs as a limiting factor.