Potentially dumb water level question

[jandb]

Hello. I should definitely know this but I'm at a loss. Here's the back story. I haven't done a water change on my 340 gallon tank for quite awhile because I now drip ~30 gpd. That said, it's a dirted/planted tank and my buddy just helped me rescape it. I vac'd and did about a 25% water change to help the cloudy water. I normally would shut the overflow valves in the sump and fill the display to the operating height or a touch higher. When I open the valves and restart the pump after an initial surge the display tank is always at about that height as I filled it. When I did this twice this morning the display tank water level was lower than I wanted, barely over the overflows. What do you think?

 

[coryjac0b]

When using a sump the display is usually at a constant height if the return flow is constant. The variable is the water height in the sump. What style overflow are you using? Also, does your return flow/pump seem normal? Is there anything restricting the flow?

 

[jandb]

When using a sump the display is usually at a constant height if the return flow is constant. The variable is the water height in the sump. What style overflow are you using? Also, does your return flow/pump seem normal? Is there anything restricting the flow?

Thanks. Yep, I get all of that. That's what is confusing me.

It's an old durso setup, 1" drains with a Mag 18 at about 9' head.

 

[coryjac0b]

If there is no otherwise typical noise, my bet would be something is restricting the flow back to the display. Maybe check the pump volute? Not sure what else to suggest. A higher than normal would indicate the drains can't keep up. A lower than normal would suggest that not enough water is being pumped back into the display.

Just my .02

 

[jandb]

If there is no otherwise typical noise, my bet would be something is restricting the flow back to the display. Maybe check the pump volute? Not sure what else to suggest. A higher than normal would indicate the drains can't keep up. A lower than normal would suggest that not enough water is being pumped back into the display.

Just my .02

Yep, thanks. That makes compete sense. I cleaned the sponge on the pump last night. I guess all the particles from the rescape could be slowing it prematurely. I'll try again when I get home.