Sump very full

Hi, I just set up a sump for my new 58 gallon with a 20 gallon long for the sump. It ran just fine for the first couple of weeks. Now all of a sudden, it seems, the sump is so full, the water just flows over the baffles with no over under action. The level of the display tank is just at the bottom of the trim. The tank has a built in overflow, drilled holes in the bottom of the tank. The downspout is the Durso type. Any suggestions? At a loss here. Especially since it changed. The return pump used to run low on occasion and shoot bubbles out the returns.
Drowning Seaponygirl

I can look see, if your going to be around when I go to Cammies tomorrow?

Is the water in the sump at the same level as when you have the return pump off for feedings or cleanings? I assume you have checked the return pump and it is running normally with normal output?

If your skimmer is running at a lower than normal set point the water that would have been in the skimmer will drain into the sump resulting in a higher than normal level.

Do you have an ATO? Issues with the level sensors so it is filling too high?

That's all I can think of. Return pump off, skimmer not full, ATO issues.

Maybe check the salinity to see if it has changed from too much water topped off. Paul, great to see some posts from ya! I believe she is manually topping off. Sue once you figure it out, if you haven't already, it's a good idea to mark where your water level should be. I have a feeling it's related to your return pump. Let us know if you figure it out.

I got it a little lower, by dipping some out of the sump. Now at least it goes over and under the baffles. When the return is off the display and sump level off and no overflows.
When you add top off water does it go in the display for the sump or does it matter. It seems when I did a water change and put the new in the sump that's when my problem began. Or it could just be me. If the water level in the display is too high and a lot is going down the durso tube would that make the sump too full?
I'm starting to understand the sump process, but still need some fine tuning knowledge.
thanks

You should fill it to where it works best and then mark that spot on your sump. Then, when you top-off, you fill just to the mark you have made. (Tape on the outside is what I did.)

Then, when you do a water change, it helps to take out a measured amount. For instance I always do my 5g buckets filled to the about the same point. And, put back in the same amount of new water. I always even top my tanks off before I do a water change so I know the levels will be right when I turn everything back on.

I hope this helps.

As to where your top off water goes...

When your system is running your return pump keeps your display tank "full".  Your display tank overflows at a set level and your return pump forces it to stay at that level.  This causes variations in total water volume to show up in the sump not the display tank. Evaporation and top off will both show up in the sump.

Within the sump any section with an overflowing baffle acts the same way as the overflow in the display tank, forcing the water level to stay constant in that section.  So when your tank is running all evaporation and top off will show up in the section of the sump that contains the return pump. It evaporates from all over, but the return section of the sump is the only part of the system where the water level can fluctuate.

I agree with Cammie and I have my sump marked the same way, all though I use an ATO.  The high mark is where I have the switch to stop filling.  If you don't already make sure you add your topoff to the return section of the sump and fill it to your mark, that way you know how much you are adding.

I would also add another mark to your sump.  Get it where you want it running, with as much water as you would have after a fresh top off.  Then power everything off, wait for it to settle out, and mark that spot.  That is your power off high level, don't exceed that if you are doing a water change with everything off and you won't get a wet floor.

If this is stuff you already know I apologize for the level of detail, but it can be confusing figuring out how the water levels are controlled.

I can't be told too often, unless it's about dog breeds. LOL Great tips. I have not been adding the water in the right spot. So I will mark them tonight.
Stopping overflow would be great. Friday night, thank God I was home, the overflow pipe came loose and started some serious splashing. Got that fixed then Sploosh, the return hose disconnected and water really gushed out. Needless to say, some of the veneer on my stand is curling. I put a huge fan, directed on the corner, to dry out the wood. It took 3 days.
Hey, that's why I call myselft the Queen of Overflow!
Yikes! Stripes!

You know, I have never thought of marking the power off level in my sump and that makes a lot of sense. Thanks for the tip.