New tank gurgle

[seerad]

Hello! I’ve upgrading from a smaller AIO unit (29g Biocube) to a custom 75 gallon setup. It’s my first time with a sump and I have some questions I’m hoping someone can help me with:

1. I feel like my display water level isn’t as high as the previous owners was based on where the water line on the glass was. I tried increasing but it just increased the amount of water in my sump. Is there a solution here?

2. my return is making a lot of gurgling sounds, is there a way to fix this? I’ve tried playing with the flow from the return pump and didn’t notice a difference.

3. my sump seems really full. I see marks for how high he was running it previously, but I also see where the water level line is on the 3rd chamber.

here are some photos. As always in this forum, thanks for any help/insights

Photos:
plumbing setup
Water level
Sump level

 

[MarineandReef Jaron]

You are going to be limited with how quiet you can get with a single drain. Does your drain line have a constant sound or does the sound pulse? (Comes and goes)

 

[seerad]

You are going to be limited with how quiet you can get with a single drain. Does your drain line have a constant sound or does the sound pulse? (Comes and goes)

It seems pretty steady. It sounds like a bathtub draining

 

[MarineandReef Jaron]

You might be about as quiet as you can get. The best you can do is put a muffler on top of the T on the outside of the tank but it looks like you already have one.

 

[Jekyl]

For the sump level being high and tank low, sounds like you need to increase the speed of the return. It's a balancing act.

 

[hoffmeyerz]

Your tank is plumbed different from mine so someone can correct me if I'm wrong but the water level in the display is set by the weir on the overflow box. The water level will increase until it overflows through the weir into the overflow box and into the drain lines.
As for the gurgling, you can try snaking some airline tubing down the drain line from the overflow, if you can get the line to hit where the air gets trapped it will give it a quiet path to escape.
Cool looking tank, hope you get it worked out. Keep posting updates!