How much water in sump/return??

[Jcs401]

I have a 24g nano with 3 chambers in rear like most. First chamber I have a protein nano skimmer, second is carbon and those acrylic ceramic things in a bag, third is the return. My question is how much or how high should those chambers be filled with water? All the way to the top, half, less not sure?? Any advice would help. Thanks!

 

[jeffaquarius]

Most nano tank have indicator at the back of the display area which say Max and MIn level. If not as long as level is not more than 2 inches below the top and circulating pump is not blowing air bubble. The level at the sump will adjust and it's better to open up the chamber gates all the way.

 

[Jcs401]

It does have an indicator on the back of the area of display, however I use a surface skimmer to correct level in the sump and am not sure what the sump level should be due to no indicator back there??