Help tuning coralbox skimmer

[Areeflover]

Could y’all help me tune my coralbox skimmer bought it used.. it works.. just not sure how to accurately and effectively tune it.
Also I just turned it on 2 days ago.

 

[X-37B]

I had to go look at my 300 in the garage to remember, lol.
I ran it on my nano for 3 years.
First is to determine the correct water level to run it at.
The only adjustment is the gate valve.
Open it all the way and then close it slowly to achieve desired skimming.
Mine was finiky but did skim well.
I had to set it on 4 pieces of eggcrate to get the required water height.

 

[Areeflover]

I had to go look at my 300 in the garage to remember, lol.
I ran it on my nano for 3 years.
First is to determine the correct water level to run it at.
The only adjustment is the gate valve.
Open it all the way and them close it slowly to achieve desired skimming.
Mine was finiky but did skim well.
I had to set it on 4 pieces of eggcrate to get the required water height.

Okay that must be my biggest issue water level

 

[ksed]

What is your water height in the sump?
And which model CoralBox is it?